February 25, 2012

Wind advisory in effect for Saturday for Baltimore region

The National Weather Service has a wind advisory in effect until 6 p.m. Saturday for the Baltimore area.

A wind advisory means that wind gusts over 45 mph are expected, and can make driving difficult, especially for “high-profile” vehicles.

The weather service is forecasting winds of 20 to 30 mph, with gusts up to 50 mph. Forecasters say the strongest winds will be Saturday morning and afternoon. They advise motorists to use extra caution.

Otherwise, the weather service is calling for Saturday to be mostly sunny, with a high near 49. There is a slight chance of showers before 2 p.m., then a chance of scattered showers and snow showers between 2 p.m. and 4 p.m. Little or no snow accumulation is expected.

Baltimore Gas and Electric said it was “closely monitoring the winds, which the utility said in a statement “could very likely cause trees and tree limbs to fall onto power lines and other electric delivery equipment.” BGE has increased the amount of repair workers in the field.

Around 11:30 a.m., the utility reported 1,143 outages in its coverage area.

Saturday night is expected to be mostly clear, with a low around 33 and west winds between 10 and 20 mph.

Sunday is expected to be sunny, with a high near 47 and northwest winds between 5 and 8 mph, becoming southwesterly.

Sunday night is expected to be mostly clear, with a low around 34 and south winds around 5 mph.

Posted by Kim Walker at 11:34 AM | | Comments (0)
Categories: Forecasts

February 11, 2012

High winds forecast for Sunday

With a night of howling winds up to 47 miles per hour and some flurries in the forecast, utility crews were preparing Saturday for potential power outages, Meredith Cohn reports.

Mostly sunny skies were forecast for the Baltimore region on Sunday, and the daytime high was expected to reach 35, according to the National Weather Service.

The winds were expected to continue blowing throughout the day and into the evening, with gusts up to 37 miles per hour, according to the service. Conditions, however, were expected to improve during the work week, with high temperatures after Monday in the 40s, reaching 51 on Thursday, when there is another chance of precipitation.

But the high winds forecast for Saturday night and Sunday led Baltimore Gas and Electric Co. to prepare for power outages. Gusts could bring down trees and limbs onto power lines and other power equipment.

BGE said it has crews on hand to respond. "BGE is proactively preparing for the likelihood of wind-related power outages by not only keeping a close watch on the weather, but also by increasing its number of field personnel overnight to assist in restoration work should outages occur," said A. Christopher Burton, senior vice president of gas and electric operations and planning for BGE, in a statement.

"Restoration work involving the removal of tree debris can be labor and time intensive," he said. "In addition, windy conditions could limit restoration work involving bucket trucks. We thank our customers in advance for their cooperation and understanding."

BGE officials warn that special needs customers should make arrangements and those with generators should make sure they are well ventilated.

Customers can report outages at 877-778-2222 and downed lines at 410-685-0123.

Posted by Kim Walker at 7:43 PM | | Comments (0)
Categories: Forecasts

February 7, 2012

Inch of snow forecast for Wednesday, starting in late morning

From The Sun's Steve Kilar:

Baltimore may see about an inch of snow Wednesday, beginning in the late morning, though the main band of precipitation is expected to cross over the city and Interstate 95 during the evening rush hour, according to the National Weather Service.

Continue reading "Inch of snow forecast for Wednesday, starting in late morning" »

Posted by Kim Walker at 10:27 PM | | Comments (0)
Categories: Forecasts

February 4, 2012

Rain, snow, but no accumulation, forecast for tonight

A chance of rain and snow is forecast for the Baltimore metropolitan area Saturday night, but snow was already falling in some parts of the area by late afternoon, according to the U.S. Weather Service in Sterling, Va.

Check out our updated weather forecast for the latest. 

Posted by at 4:13 PM | | Comments (0)
Categories: Forecasts

January 14, 2012

Chilly game day for Ravens fans

Bring blankets and hand warmers and wear your wool socks if you plan on going to Sunday's Ravens game. The National Weather Service is calling for a high of 34.

Baltimore professional meteorologist Eric the Red thinks it will be colder than that:

"A rather non-descript arctic front will drift south thru the region [Saturday night] and weaken, but its impact will be notable. ... A northerly wind will signal its passage, and temperatures on Sunday will now struggle to get out of the middle and upper 20s." 

Posted by Kim Walker at 11:04 PM | | Comments (0)
Categories: Forecasts

November 18, 2011

Friday's forecast: Sunny, high 46

The National Weather Service is calling for Friday to be sunny in the Baltimore area, with a high near 46 degrees and west winds of 5 to 9 miles per hour.

A small craft advisory is in effect until 11 a.m. Friday for the Maryland portion of the Chesapeake Bay, including all inlets, as well as the lower tidal Potomac River.

Friday night is expected to be clear, with a low around 35 and south winds of 3 to 6 miles per hour.

Saturday is expected to be sunny, with a high near 53 and south winds between 5 and 10 miles per hour.

Saturday night is expected to be partly cloudy, with a low around 43 and south winds between 5 and 7 miles per hour.
Posted by at 7:16 AM | | Comments (0)
Categories: Forecasts

November 17, 2011

Thursday's forecast: Showers, high 47

The National Weather Service is calling for Thursday to be rainy in the Baltimore area, with a high near 47 and northwest winds of 9 to 14 miles per hour. The chance of precipitation is 100 percent.

A small craft advisory is in effect Thursday and Thursday night for the Maryland portion of the Chesapeake Bay, including all inlets, as well as the tidal Potomac River.

Thursday night is expected to be mostly clear, with a low around 34 and west winds around 10 miles per hour.

Friday is expected to be sunny, with a high near 47 and west winds between 6 and 8 miles per hour.

Friday night is expected to be clear, with a low around 34 and south winds between 3 and 5 miles per hour.
Posted by at 6:38 AM | | Comments (0)
Categories: Forecasts

November 16, 2011

Wednesday's forecast: Rainy

The National Weather Service is calling for Wednesday to be rainy in the Baltimore area, with a high near 63 degrees and winds becoming northerly between 6 and 9 miles per hour. Scattered thunderstorms may develop, mainly south of the Baltimore area, with a few becoming severe and bringing damaging winds.

The chance of precipitation is 100 percent. Rainfall amounts of between one quarter of an inch and half an inch are possible.

A small craft advisory is in effect until 11 p.m. Wednesday for the Chesapeake Bay from Drum Point to Smith Point, Tangier Sound and the lower tidal Potomac River from Cobb Island to Smith Point. A small craft advisory is in effect for all of the bay Wednesday night.

Wednesday night is expected to be rainy, with a low around 47 and north winds between 7 and 16 miles per hour. The chance of precipitation is 100 percent. Rainfall amounts of between half an inch and three quarters of an inch are possible.

Thursday is expected to start with showers and then gradually become clear, with a high near 51 and northwest winds of 11 to 14 miles per hour, gusting up to 24 miles per hour. The chance of precipitation is 60 percent.

Thursday night is expected to be clear, with a low around 34 and west winds between 8 and 10 miles per hour.
Posted by at 6:53 AM | | Comments (0)
Categories: Forecasts

November 14, 2011

Monday forecast: Partly sunny, high 68

The National Weather Service is calling for Monday to be partly sunny in the Baltimore area, with a high near 68 degrees and south winds of 10 to 14 miles per hour and gusts up to 24 miles per hour.

A small craft advisory is in effect through Monday evening for the Maryland Chesapeake Bay and the tidal Potomac River. A small craft advisory is in effect for late Monday night for the lower tidal Potomac River and for the Maryland Chesapeake Bay from Sandy Point to Smith Point.

Monday night is expected to be mostly cloudy, with a low around 57 and southwest winds of 7 to 13 miles per hour. There is a 20 percent chance of precipitation.

Tuesday is expected to be cloudy, with a high near 66 and west winds of 5 to 7 miles per hour. The chance of precipitation is 40 percent.

Tuesday night is expected to be cloudy, with a low around 50 and east winds between 4 and 7 miles per hour. There is a 60 percent chance of precipitation. Rainfall amounts between one half of an inch and three quarters of an inch are possible.

Posted by at 7:31 AM | | Comments (1)
Categories: Forecasts

November 11, 2011

Forecast: Sunny and breezy, high near 52

The National Weather Service is calling for Friday to be sunny and breezy in the Baltimore area, with a high near 52 and west winds of 14 and 20 miles per hour, with gusts as high as 31 miles per hour.

A gale warning is in effect for the lower tidal Potomac River and the Maryland portion of the Chesapeake Bay south of Drum Point. A small craft advisory is in effect for the Chesapeake Bay through Friday night.

Friday night is expected to be mostly clear, with a low around 34 degrees and calmer west winds of 4 to 7 miles.

Saturday is expected to be sunny, with a high near 60 and southwest winds of 7 to 13 miles per hour.

Saturday night is expected to be partly cloudy, with a low around 43 and south winds of 5 to 8 miles per hour becoming calm.
Posted by at 6:43 AM | | Comments (0)
Categories: Forecasts

November 10, 2011

Thursday forecast: Morning fog advisory

The National Weather Service is calling for Friday to be mostly cloudy in the Baltimore area, with a high near 56 and light winds becoming northwesterly of 12 to 15 miles per hour. The chance of precipitation is 20 percent.

A dense fog advisory is in effect for central and southern Maryland until 9 a.m. Thursday, meaning visibility may be reduced to one quarter of a mile or less. A small craft advisory will be in effect for the tidal Potomac River and the Maryland Chesapeake Bay Thursday afternoon and night.

Thursday night is expected to start mostly cloudy and then gradually become mostly clear, with a low around 39 degrees and west winds between 9 and 15 miles per hour.

Friday is expected to be sunny and breezy, with a high near 53 and west winds between 16 and 21 miles per hour.

Friday night is expected to be mostly clear, with a low around 38 and west winds of 5 to 13 miles per hour. 

Posted by at 7:27 AM | | Comments (0)
Categories: Forecasts

November 9, 2011

Wednesday's forecast: Sunny, high 68

The National Weather Service is calling for Wednesday to be sunny, with a high near 68 degrees and winds becoming southeasterly between 4 and 7 miles per hour.

Wednesday night is expected to be cloudy, with a low around 49 and south winds of 3 to 5 miles per hour. There is a 20 percent chance of precipitation.

Thursday is expected to be mostly cloudy, with a high near 58 and winds becoming northwesterly between 10 and 13 miles per hour. There is a 30 percent chance of precipitation.

Thursday night is expected to start out cloudy and then clear up, with a low around 41 and west winds between 11 and 14 miles per hour. The chance of precipitation is 30 percent.
Posted by at 7:11 AM | | Comments (0)
Categories: Forecasts

November 8, 2011

Tuesday's forecast

The National Weather Service is calling for Tuesday to be sunny in the Baltimore area, with a high near 67 degrees and winds becoming southeasterly around 5 miles per hour.

Tuesday night is expected to be clear, with a low around 49 and calm winds.

Wednesday is expected to be sunny, with a high near 65 and winds becoming southerly between 5 and 8 miles per hour.

Wednesday night is expected to be mostly cloudy, with a low around 52 and south winds of 3 to 6 miles per hour. There is a 20 percent chance of precipitation after 1 a.m.

Posted by at 7:38 AM | | Comments (0)
Categories: Forecasts

November 7, 2011

Monday's forecast

The National Weather Service is calling for Monday to be sunny in the Baltimore area, with a high near 64 degrees and light, variable winds.

Monday night is expected to be clear, with a low around 45 and calm breezes.

Tuesday is expected to be sunny, with a high near 65 degrees and light north winds.

Tuesday night is expected to be mostly clearly, with a low around 50 and calm winds.

Posted by at 7:44 AM | | Comments (0)
Categories: Forecasts

November 4, 2011

Friday's forecast

Happy Friday! Here's your forecast:

The National Weather Service is calling for Friday to be sunny in the Baltimore area, with a high near 58 degrees and north winds of 9 to 15 miles per hour.

A small craft advisory is in effect Friday and Friday night for the Maryland Chesapeake Bay and the tidal Potomac River.

Friday night is expected to be clear, with a low around 36 and north winds of 9 to 13 miles per hour.

Saturday is expected to be sunny, with a high near 53 degrees and northeast winds around 10 miles per hour.

Saturday night is expected to be clear, with a low around 39 and east winds between 3 and 5 miles per hour.

Posted by at 7:03 AM | | Comments (0)
Categories: Forecasts

November 2, 2011

Wednesday's forecast

The National Weather Service is calling for Wednesday to be sunny in the Baltimore area, with a high near 61 degrees and winds becoming south around 6 miles per hour.

Wednesday night is expected to be mostly clear, with a low around 40 and south winds between 3 and 5 miles per hour.

Thursday is expected to be sunny, with a high near 61 degrees and southwest winds of 5 to 7 miles per hour.

Thursday night is expected to be mostly cloudy, with a low around 45 and south winds at 6 miles per hour becoming northwesterly.

Posted by at 7:05 AM | | Comments (1)
Categories: Forecasts

October 27, 2011

Freeze watch posted tonight for northern counties

We're in for a drippy day today in Central Maryland as we wait for the next cold front to moveNWS through late this afternoon. And once it finally gets by us, we're in for some of the first really nippy temperatures of the season.

The National Weather Service forecasters at Sterling have posted a Freeze Watch for the early hours of Friday morning, from Allegany County across Maryland's northern tier of counties to northern Baltimore County and Harford (dark blue on the map). The city and southern Baltimore County are not included. The forecast low for BWI tonight is 38 degrees.

Low temperatures in the watch zone will reach the low 30s, forecasters say. "A Freeze Watch means sub-freezing temperatures are possible. These conditions could kill crops and other sensitive vegetation."

AccuWeather.comFriday still looks good, with sunny skies. But daytime highs will only reach the low 50s. And the forecast from there goes downhill again.

Another low pressure system arrives from the Carolinas late Friday and Saturday just as a new surge of cold air moves through the region. Forecasters expect a cold and rainy coastal storm to develop, with Saturday's highs only in the 40s at BWI, and an 80 percent chance of rain.

"Hate to mention it," this morning's forecast discussion adds, "but precipitation initially falling into a rather chilly air mass ... which will only be enhanced by evaporative/diurnal/dynamic cooling processes. Thus, need to consider elevation-dependent snow or snow/rain mix during the late night/early morning hours. ... Changing to snow around 1,500 feet."

For Central Maryland, puts the rain/snow line well to our north, somewhere around Philadelphia. They also add some storm-track uncertainties. Here's their discussion of the Saturday storm possibilities.

Whatever, looks like a good day for a book and a fire in the fireplace. Or a pub.

Posted by Frank Roylance at 11:05 AM | | Comments (2)
Categories: Forecasts

October 26, 2011

Weather turning colder, wetter

Near 70 today; 60s Thursday; 50s Friday. That's how the forecast from Sterling goes this afternoon. And they're throwing in rainy days for Thursday and Saturday for good measure as a AccuWeather.comcold front and coastal low affect the region.

The most interesting thing in the seven-day predictions from the NWS is the temperature drop. Central Maryland will be looking at overnight lows in the 30s by Thursday night into Friday, after daytime highs sink from near 70 today, to the 50s on Friday. 

Low pressure tracking along the front will encounter that cold air early Friday, "That could provide a brief period of snow showers or snow/rain showers at the conclusion," forecasters said today, especially in the western mountains. The real accumulating snow will fall well to our north, as the map above shows.

After a sunny day Friday, they're expecting a coastal low to move this way, running into still-cold air at the surface. "There's still uncertainty as to how everything will unfold," forecasters said. "And since boundary layer temps still on the cool side, am also uncertain as to what form precipitation would come overnight as if it did fall. Would stay tuned to the Friday night/Saturday forecast..."

Sunday looks sunny and nice, as do the first days of the new work week, with daytime highs creeping back up through the 50s.

Posted by Frank Roylance at 12:06 PM | | Comments (0)
Categories: Forecasts

October 25, 2011

Clear tonight, but rain/snow mix hinted in forecast

Looks like these clear skies will hold into this evening, opening a slim chance of seeing some more of the northern lights that reached down into Maryland and beyond on Monday night. Later in the week, forecasters are calling for showers, colder temperatures and even a risk of some wet flakes in the mix.

The high pressure bringing us these clear skies and sunshine will drift to the southeast. That will AccuWeather.comadmit some increasing cloudiness early Wednesday. Temperatures could reach 70 degrees - the last we'll see of that number for a while.

The arrival of a cold front Wednesday will open the door to a storm system that forecasters say will deliver showers beginning early Thursday morning, and continuing into Thursday evening. 

And there the forecast models diverge. One predicts enough cold air moving in behind the front to change rain showers into snow showers, at least in the western mountains. Others see no such problems ahead. Here's on the prospects.

Partly sunny skies return on Friday, but a new low forms along the coast, bringing a renewed threat of rain showers Friday night into Saturday. Daytime highs on Friday at BWI-Marshall Airport won't leave the mid-50s. The forecast lows from Thursday night through Sunday night are in the 30s. (Have you switched on the furnace yet?)

The NWS forecast discussion for Friday night into Saturday says: "Best chances for precipitation will be eastern zones, and gradient likely will be sharp. Possibility for mix of rain/snow will have to be monitored, if airmass proves sufficiently cold."

For now, at least, the official predictions for mixed precipitation are limited to higher elevations and portions of north-central Maryland.

Posted by Frank Roylance at 11:47 AM | | Comments (0)
Categories: Forecasts

October 24, 2011

Showery midweek will yield to "fallish" weekend

A pair of cold fronts will punctuate the week for Central Maryland, ushering in a fine day on Tuesday, a rainy couple of days at mid-week, followed by a sunny and cool autumn weekend.

The first frontal system is due through the region Monday afternoon, ending a mostly cloudy dayAutumn in Baltimore with mild temperatures borne on southwest winds. The southerly component of the wind has triggered a Coastal Flood Advisory, but forecasters are expecting the water to rise only a foot or less above tide table predictions for Arundel's shores. 

This evening's cold front is draped south from a low-pressure center moving across Canada. Scattered showers may accompany the front, especially north and west of the urban corridor, forecasters said. 

By this evening, the front will have moved across the Chesapeake, and we'll start to get cooler, drier air moving in from the west-northwest. Lows tonight will sink back to the 40s.

Tuesday looks perfect, with sunny skies and highs in the mid-60s. If you have a mental health day coming, take it.

AccuWeather.comShower chances rise again on Wednesday ahead of the next cold front and an accompanying low-pressure system, especially for the northwest suburbs. The cold front settles in by Thursday morning, with lots of clouds and shower chances rising to 60 percent. is making quite a lot of this event. The NWS is much more ho-hum, at least for Central Maryland. Eric the Red has even ventured the S-word. (See jump, below.)

Once that front moves out, the weather will turn cooler, drier and blustery, as colder Canadian air moves in behind it, forecasters said. High temperatures Friday and through the weekend will stall out in the mid-50s, which is 5 or 10 degrees below the seasonal averages. Lows will drop into the 30s Saturday night into Sunday.

A perfect weekend ahead for a fall walk in the woods. 

(SUN PHOTO: Amy Davis, November 1994)

Continue reading "Showery midweek will yield to "fallish" weekend" »

Posted by Frank Roylance at 11:39 AM | | Comments (0)
Categories: Forecasts

October 19, 2011

Eric the Red calls for near-normal snowfall ahead

One of our regular forecast contributors here, a professional Baltimore meteorologist we call Eric the Red, has posted his winter weather forecast for the season coming up. And like the forecast issued a few weeks ago, he expects another near-normal snow total this time around.

The 30-year average snow total for BWI-Marshall Airport is 20.2 inches. Last winter saw 14.4 inches.

Taking account of the La Nina conditions developing in the Pacific for the second winter season in a row, as well as a basket of other climate factors, Eric says the signs this year point to "near- to below-normal snowfall, just like last year, but not a snowless winter."

Looking for winters when similar conditions prevailed, he found these Baltimore analogs: SNow Baltimore 2011

1950:  6.2 inches

1962:  19.6 inches 

1974:  12.2 inches

1985:  15.6 inches

2008:  9.1 inches 

"All these winters are consistent with the reasoning of near- to below-normal snow. In addition, La Nina is associated with near- to below-normal temperatures in the central and eastern U.S. and tends to be windy here, too," he said.

"The wild card is the NAO [North Atlantic Oscillation], which has been consistently negative (a blocking high over the northern Atlantic) for the past several winters ... and this can change everything. If and where the block(s) set up can throw a serious monkey wrench into the equation - think New England last year, our record-setting winter 2 years ago.

"A blocking high/negative NAO is almost essential for big snows around here, and forecasting this feature is not feasible beyond several weeks. Persistence implies that we will be dealing with it again, however."

The National Oceanic and Atmospheric Administration will issue its winter weather forecast Thursday. Stay tuned.

(SUN PHOTO: Amy Davis, Jan. 26, 2011)

Posted by Frank Roylance at 3:06 PM | | Comments (1)
Categories: Forecasts, Winter weather

Severe weather threat later today

Forecasters have dialed back their predictions for rain totals from the twin lows that will be affecting Central Maryland Wednesday. But there remains some threat of severe weather for some locations later in the day. Moderate coastal flooding may also become an issue as winds persist out of the east and northeast, swinging to the south tonight.

The National Weather Service forecasters out in Sterling, Va. are expecting no more than a half-AccuWeather.cominch of rain at BWI-Marshall Airport Wednesday and Wednesday night. But if you happen to come under a thunderstorm, you could see more. SOme Eastern Shore Locations are seeing more, with three-quarters to almost an inch of rain in the gauges, according to the CoCoRaHS Network.

We're getting reports of numerous highway accidents around the region this morning, and wondering whether rain, reduced visibility and fallen leaves may be a contributing factor. Baltimore County alone is reporting three separate smashups on the Beltway in the Pikesville area, one of them involving five vehicles, with injuries.

The severe weather later Wednesday would come in the form of fast-moving lines of thunderstorms developing after mid-day. They could bring damaging winds and/or urban flooding.

Wind shear conditions aloft could also allow for some tornado development as well. Time to set your NOAA Weather Radio to "Alert."

There is a coastal flood warning in effect after 7 p.m. Wednesday for the Western Shore from Calvert County northward. High tides could rise about two feet above predicted levels. 

The coastal low over eastern Georgia this morning will merge or "phase" with a Midwestern low today as they reach the mid-Atlantic states. And as the system moves off to the northeast overnight, we should begin to see the rain end. Getting rid of the clouds on Thursday may take longer, however. Showers may linger west of the mountains, forecasters said. Elevations above 2,500 feet could see snowflakes, but no accumulation.

By Friday, we should be in the clear everywhere, with prospects good for a fine autumn weekend, with sunshine and highs in the low 60s.

Posted by Frank Roylance at 11:06 AM | | Comments (0)
Categories: Forecasts

October 18, 2011

Rain arrives tonight, stays through Weds.

Another beautiful start to the day out there, but forecasters say we can expect high clouds to begin moving in later Tuesday, then lowering, and delivering the first showers during the wee hours of Wednesday morning.

Showers, perhaps some thunderstorms, and more showers are forecast to continue through the day Wednesday and well into the early morning hours of Thursday. More than an inch is possible AccuWeather.combefore the twin lows headed this way finally merge and depart to the northeast. Some western counties could see some wet snowflakes before it's all done - or "snizzle" as the folks out at NWS/Sterling are calling it.

The rest of the week, and through the weekend, looks fine, with sunny skies and highs slightly below the long-term averages, in the upper 50s and low 60s.

Here's the plan: Forecasters now see the tropical disturbance in the Gulf of Mexico as a fizzle as far as becoming a tropical storm. But it will send loads of Gulf and eventually Atlantic moisture up the coast in the next couple of days. The low itself will arrive in time to "phase" or merge over the Chesapeake with another low moving this way after pummeling the upper Midwest with cold winds and rain.

The combined lows are forecast to deliver significant precipitation and considerable winds for Central Maryland. There will be enough energy for some isolated thunderstorms through the period, and some small risk of tornadoes from the bay east, forecasters said.NWS

Once the lows merge and head off to the northeast early Thursday morning, skies will start to clear and dry out. Winds will be gusty out of the southwest, then the west, as high pressure begins to build into the region. Forecasters said this morning they have "reintroduced snow for late Thursday night [on the Allegheny front] ... more like snizzle - very small ice and snowflakes from a very low cloud or fog." 

East of the mountains, they're calling for gusty winds Thursday, with overnight lows early Saturday and Sunday mornings, dipping into the upper 30s or low 40s east of the mountains.

Posted by Frank Roylance at 11:09 AM | | Comments (0)
Categories: Forecasts

October 17, 2011

Enjoy the sun; clouds, rain en route

Not much to complain about today - aside from it being Monday and the end of my vacation, I mean. Forecasters are looking for highs in the 70s and plenty of sunshine behind the weak cold Bugfront that pushed through this morning and took the clouds with it.

Unfortunately, that front will return Tuesday as a warm front, bringing increasing clouds and the threat of rain as a low pressure system out of the Gulf pushes our way.

By Tuesday night, forecasters say we'll be looking for showers and perhaps an overnight thunderstorm. They're calling for as much as a quarter-inch of rain, or possibly more in thunderstorms. Rain chances will continue at 80 percent Wednesday, with more chances for thunderstorms into early Thursday morning.

Some of the storm's moisture will be coming in a stream of moisture drawn out of a tropical system developing now near the Yucatan. That could make weather news from Ohio into the Northeast. Here's's take on that

By Thursday the low will be exiting to our northeast, and we'll begin to feel northwesterly winds. That will start to dry us out and usher in a weekend of clear skies and cooler temperatures, with near-normal weekend highs in the 60s at BWI. Western counties could see some light accumulating snow in the higher elevations Thursday night. Our lows will hold in the low 40s.

(SUN PHOTO: Katydid, Frank Roylance)

Posted by Frank Roylance at 11:12 AM | | Comments (0)
Categories: Forecasts

October 3, 2011

No really... the sun will come out, tomorrow

I know, forecasters have been promising sunshine for a week. The stubborn cut-off low that has been controlling much of our weather for nearly two weeks was supposed to move out of the Midwest, across the mid-Atlantic and up into New England by now. High pressure would build in from the west and our long regional nightmare of gray skies and showers would be over.

Except that it hasn't happened. Not yet, anyway. That low has moved east. And now it's parked on top of us. The sunny weekend they predicted has come and gone, with downright cold Gray day in Baltimoretemperatures and showers and wind instead.

UPDATE, 3 p.m.: Sunday's high of 51 degrees at BWI-Marshall Airport broke the previous record-low maximum temperature for the date - 53 degrees, set in 1939. 

Admit it; you were tempted to switch on the furnace this weekend. Am I right? At least you weren't dealing with snow, as some were in West Virginia this weekend.

The new forecast promises that all this, too, will pass. After more light showers and gray skies Monday, forecasters said, "The reign of this feature is slow[ly] coming to an end."

"Much of the eastern half of the country, especially the Ohio Valley/mid-Atlantic/New England has been under the influence of this upper-level system for the past couple of weeks. Today will be the slow-steady passage, and tomorrow the wind ... Improvement in these conditions [is] on the way, but it will be another day or two. Today will be cloudy and fairly wet, and tomorrow mostly cloudy and breezy."

The computer models, at least, seem to agree that the low will be clearing out overnight,  with some breaks in the clouds. Increased sunshine Tuesday will begin to raise daytime temperatures out of the 50s, where they resided all weekend, into the upper 60s Tuesday. There remains a "slight" chance for showers Tuesday, but any that do form will be light, they say.

The rest of the week looks fine, with sunny skies Wednesday and right through the weekend. Temperatures will improve gradually, moving back into the low 70s, which is about where they belong at this time of year in Baltimore.

They promise.

(SUN PHOTO: Frank Roylance)

Posted by Frank Roylance at 11:08 AM | | Comments (1)
Categories: Forecasts

September 30, 2011

Or not ... Gray, rain may return for weekend

Seems like only yesterday that forecasters were promising some sunshine with the cool temperatures this weekend. In fact, it was Wednesday.

AccuWeather.comWell, all that seems to have gone away now. The National Weather Service folks in Sterling now say the same low-pressure system that has been powering our nearly incessant clouds and showers all week STILL has not left the premises.

We're enjoying a fine break today. But the low-pressure system, while it has moved east a bit from Lake Michigan, is now loitering in the eastern Great Lakes. And clouds are just to our west, poised to move in. 

Now forecasters say the low will hang out to our north this weekend. Combined with a new coastal low that's forming, we can expect increasing clouds and showers starting late Friday.

Temperatures will be falling, too, reaching the 30s - with a chance for rain and wet snow in the higher elevations to our west - to the 40s in the western suburbs and 50s along the Western Shore. (The "RealFeel" temperatures in the map above are AccuWeather's system for combining effects of temperature, humidity, wind, elevation and other factors to express how conditions will "feel.")

The forecast calls for more of the same Saturday and Sunday, with the added feature of daytime temperatures only in the 50s as colder air rushes in.

Forecasters are still saying the new workweek should bring sunny skies as the big bad low FINALLY departs. Temperatures will begin to moderate, reaching 70 degrees or so by Tuesday and Wednesday.

Posted by Frank Roylance at 11:57 AM | | Comments (3)
Categories: Forecasts

September 29, 2011

Wet snowflakes in forecast ...

... for the Allegheny Highlands. Sorry. I couldn't resist. Although we here in Central Maryland are looking at a cool weekend, with highs only in the 50s Saturday and Sunday at BWI-Marshall Early snowAirport, there is no mention of anything frozen here. Our lows will hold in the upper 40s. The earliest snow on record for Baltimore (a trace) fell on Oct. 9, 1903.

But this morning's forecast discussion from Sterling does include this for Western Maryland:

"Forecast high temperatures Saturday below 60 F. all areas, with higher elevations barely above 40 F. Cannot rule out a few wet snowflakes Friday night, early Saturday along Allegheny Front..." Check out the map from

We're looking for more scattered showers and thunderstorms this afternoon with the passage of the first cold front. This is the western half of the system that has kept us gray and showery for the past week, and it's finally getting by us today as the jet stream scoops south, picks it up and moves it along. Finally.

Friday looks nice, with dry, partly sunny skies and seasonable highs in the mid-70s. We'll likely see a few more showers late Friday and early Saturday as the next cold front rolls by and drops our temperatures again on strong northwest winds. But then our long, soggy September will be behind us at last.

There's clear sailing ahead into next week. And the brisk weekend temperatures will moderate into the 60s and 70s as we start the new week.

Posted by Frank Roylance at 10:28 AM | | Comments (4)
Categories: Forecasts

September 28, 2011

October will arrive with a nip in the air

Forecasters are saying now that we'll finally get rid of this dank, gray weather this weekend. But October will arrive Saturday with some bite. High temperatures Saturday and Sunday are now expected to stall out in the upper 50s. The last time that happened at BWI was way back on April 22.

AccuWeather.comFirst, forecasters say, the midwestern "cut-off" low that has been sitting and spinning out there for a week, helped to drag incessant, damp, sub-tropical moisture this way from the Gulf and the Atlantic, will finally get kicked out of the region by Thursday. That will be followed on Friday by two quick waves of low pressure and increasingly strong cold fronts - each with a risk of scattered thunderstorms. Some could become severe, but they don't expect widespread severe weather.

They do expect temperatures to drop with each event, however. 

"These repeated surges of increasingly cooler air will scour out any low-level moisture and cause temperatures to drop into very autumn-like ranges," forecasters said. Northwest winds will trigger showers on the western slopes of the mountains, "some of which could become wintry Saturday night as minima fall into the 30s," they said.

There. That's our first mention of "wintry" in a forecast this season. Here's's take on flakes.

For now, however, we're just looking at more of the same. The NWS expects showers and thunderstorms, mainly after noon Wednesday. Some could become severe and produce heavy rain. Ditto for Wednesday night. Expect more of the same Thursday and Thursday night, too, as the cut-off low lumbers by.

We get a break Friday, with partly sunny skies and a high near 74, but rain risks tick up again Friday night as the last of the cold fronts goes past. The weekend still looks increasingly sunny as high pressure builds in, with cool highs in the 50s, rising into the 60s early next week. 

Posted by Frank Roylance at 10:42 AM | | Comments (2)
Categories: Forecasts

September 27, 2011

More showers, clouds, gray, blah, blah, blah

So here we are, still stuck between the same cutoff low spinning over Illinois, blah blah, blah... Bermuda high hanging off the coast, blah blah,...  preventing these systems from moving away, still combining to send warm, moist air up the East Coast from the Gulf and the Atlantic, and blah, Foggy Baltimoreblah, blah.

Have you heard this before, too? Fog, clouds, drizzle, blah, blah, blah ... A bit more rain, rainiest September, yada, yada... Cold front due, but not yet ... yada, yada.  Onshore winds, minor coastal flooding again... for a while longer...

There is relief on the way, forecasters insist ... we'll believe it when skies clear. Maybe Thursday, they claim. Sure.

Best hope we can pass along: Cold front clears the region late Thursday, skies clear by Friday, air dries out and temperatures drop. They're predicting a high Saturday of only 62 degrees - almost 20 degrees colder than today. Then sunny into next week. 

Maybe then I can cut the grass. Yay...

(SUN PHOTO: Kim Hairston, 2011)

Posted by Frank Roylance at 10:33 AM | | Comments (2)
Categories: Forecasts

September 26, 2011

Finally, dry and cool by the weekend

Looks like we're going to be stuck with this tropical humidity and a threat of showers and storms for a few more days. But if you're impatient for the cooler, drier weather that should come with the arival of autumn in Maryland, you need only wait out this week.

The National Weather Service says we can the chances for rain and showers to increase late today, Bike trailrising to 70 percent on Tuesday and 60 percent Tuesday night. Wednesday, too, could bring more showers, with chances for Wednesday night rated at 50 percent.

Thursday looks better as the cold front begins, finally, to push through. And by Friday afternoon, forecasters say, this stalled weather pattern we've been suffering with for something like a week now will finally be moving off to our east. That will get us out of the southerly flow that has been channeling tropical moisture from the Atlantic since last week, pushing our rain totals to historic levels.

By late Friday and the weekend, we should be seeing overnight lows dropping into the 40s, with daytime highs only in the low 60s - even under dry, sunny skies. Western counties could see some frost and freeze watches, forecasters say. But it will be a great weekend for the bike trail, a jog in the park or a hike in the woods. Shut off the AC, open the windows and get the place aired out.

On the down side, I'm seeing the stink bugs begin to crowd around the doorways, looking for a chance to break in. And I've already sent a handful of the intruders off to explore the city's sewer system. How about you? Are you seeing more stink bugs this fall, or fewer? Or is it still too soon to tell?

(SUN PHOTO: Lloyd Fox, 2009)

Posted by Frank Roylance at 10:42 AM | | Comments (1)
Categories: Forecasts

September 23, 2011

In for another soaking

Looks like Central Maryland will be in the chute again as stalled weather systems to our east and west conspire to channel a few more days of tropical moisture, showers, rain and thunderstorms this way.

With nearly 20 inches of rain in the bucket since the beginning of August, forecasters are saying we should prepare for as much as another 3 to 6 inches in the next few days. And the I-95 corridor could see the worst of it, if you can believe some of the forecast models.

"The model consensus for the axis of heavy rain fall is near the I-95 corridor, with west to east variability of this axis ranging from just east of the Blue Ridge to the Chesapeake Bay. Rainfall totals of 2 to 3 inches with isolated amounts of 4 to 5 inches are possible within this band, which is AccuWeather.comenough to produce flash flooding," said National Weather Service forecasters in Sterling, Va., in this morning's forecast discussion.

Flash Flood Watches are in effect for the entire Western Shore, from Frederick County east to the bay and south to the Potomac. "The best chance for the heaviest rain will be near and east of the I-95 corridor," the watch said.

UPDATE, 11:30 a.m.: A Flash Flood Warning was issued for portions fo Frederick and western Carroll counties as heavy rains crossed the area with rain rates of up to an inch an hour.

Eric the Red, a professional meteorologist in Baltimore and frequent contributor here, said this rain event won't compare with that from remnants of Tropical Storm Lee earlier this month, but he had this analysis to offer:

"Stalled upper-air low to our west and a stationary high to our east puts us between two spinning pinwheels, pulling all sorts of tropical moisture into our area. The problem with this forecast is there is no easy-to-identify trigger mechanism (no stalled front or tropical storm) ... so we're left with a ton of moisture, high rainfall potential, but nothing to grasp in terms of where this rain will fall. This is readily apparent in the models, which all have heavy rain falling, but they are all over the place as to where."

Wherever is falls, he said, "This rain will come down in torrents ... so be prepared to deal with street flooding and all the other fun that comes with this. Throw in the 10-15" of rain that has fallen over the past 2-3 weeks, and you can see why we're under a Flash Flood Watch."

Here's's take on what's ahead.

For the record, August ended with 10.38 inches of rain at BWI-Marshall Airport, the fifth-wettest on record for the city. Through midnight last night, the airport had received 9.57 inches. Three more inches this weekend would make this the wettest September on record for Baltimore, beating the 12.41 inches in 1934. 

We've had more than a foot of surplus (above average) rain since Aug. 1.

Posted by Frank Roylance at 10:32 AM | | Comments (5)
Categories: Flooding, Forecasts

September 22, 2011

Heavy rain Friday; more showers through Tues.

We just can't seem to shake these clouds and persistent chances for rain. And rains could become heavy Friday and Friday night, with several inches possible before it's over. And showers remain in bthe forecast right through the weekend. The word "sunny" doesn't return to the forecast without AccuWeather.coman accompanying threat of showers until Wednesday.

The problem remains a stubborn low over the Ohio Valley that just doesn't want to move, and an associated cold front to our west. They're combining to draw warm, moist air north from the Gulf and the Atlantic. We get clouds and showers - isolated, scattered, all varieties - and the occasional thunderstorm.

Rain 90 pctThe wettest day will be Friday, with several inches on tap for the I-95 corridor if the forecasters are right. Rain chances at put at 90 percent during the day, and 80 percent Friday night. Forecast models differ on how much to expect. But forecasters today decided to issue a Flash Flood Watch for Friday from Carroll and Harford counties south to Prince George's and Arundel. 

By the weekend, the cold front will have stalled on the coast. Central Maryland will remain in the plume of moist air from the south, and shower risks remain in the 30 to 60 percent range under cloudy skies. "Partly sunny" appears in Sunday's forecast, and again on Tuesday, both with a chance for showers. 

Had enough yet?

Posted by Frank Roylance at 11:36 AM | | Comments (3)
Categories: Forecasts

September 20, 2011

Rain persists, could be heavy by week's end

Light rains today are expected to taper off this afternoon, with a "dry" night expected Tuesday into Wednesday. But we're still in for a pretty wet week, with the possibility of some substantial rainfall by Thursday and Friday.

Who needs this, right?

Forecasters say we're stuck in a pattern of slow-moving weather systems, with rain along and AccuWeather.comahead of a cold front loitering to our west, and a stubborn high to our east that's preventing much movement of these systems through the mid-Atlantic region - a kind of meteorological constiptaion.

The result will be a rainy week as warm, moist tropical air from the Gulf of Mexico and the Atlantic is drawn north ahead of the front. Forecasters are projecting that our rain chances will increase from 40 percent on Wednesday to 70 percent by Friday. Some thunderstorms are possible by Thursday, they say, but the cloud cover will stay pretty thick, reducing the chances for sunshine to provide the heat needed to fire them up.

Forecasters seem more concerned that the cold front to our west, once it finally gets moving through our region, will set off heavier rains: "Increasing the concern for the potential of heavy rainfall across portions of the [forecast area] Thursday and Friday." blogger Elliot Abrams is showing one model that sports a prediction of 2 to 5 inches of rain across Maryland before these systems clear out. But disagreement among the forecast models leaves some uncertainty there, too.

There's also more uncertainty now about the weekend. Although the forecast looked good yesterday, there is now a 30 percent chance for rain posted for Baltimore on Saturday. The problem is the cold front, which is expected to stall this weekend somewhere on the eastern seaboard on its way out of the region. Just where it settles will determine who gets more rain and who will finally see some sunshine.

I vote for sunshine.

Posted by Frank Roylance at 11:06 AM | | Comments (1)
Categories: Forecasts

September 19, 2011

Rain risks grow this week; weekend looks sunny

Just in case you haven't had enough rain yet this month, forecasters have ginned up a pattern of increasing rain chances this week, with a "plume" of moist air headed our way out of the Gulf of Mexico. But they seem to have spared the weekend, which looks sunny, in the 70s.

For the moment, we are enjoying a high pressure system that is responsible for Monday's sunshine. But close behind it to the west there's a cold front approaching the Appalachians. It's currently draped from the parent low over the central Great Lakes, south and west to the Texas Gulf Coast.

By tonight, the high will be moving out over the western Atlantic, making room for the front to move in behind it, with its associated showers and thunderstorms.

The chances for showers and storms grow from 40 percent after 3 a.m. Tuesday morning, to 50 and 60 percent by Thursday.

The problem is this: The high we're enjoying today will move off the coast as a Bermuda High and hold there, blocking the cold front from doing its thing here, and moving on. Instead, it's expected to stall here, drawing moisture north from the Gulf and the Atlantic. As the front intensifies, we get more rain. Four days of drippy showers and storms.

At that point, Thursday night into Friday, the front will move on again, passing by sometime early Friday. And with that, rain will taper off and skies will clear for the weekend.

Posted by Frank Roylance at 11:54 AM | | Comments (0)
Categories: Forecasts

September 16, 2011

Sunny here, rainy at the beaches this weekend

This may be the weekend for folks down at the beaches to come to Baltimore and Central Maryland for a little getaway.

AccuWeather.comForecasters are calling for a cool, but sunny weekend on the Western Shore. Highs will hold in the 60s, with partly to mostly sunny skies. That's thanks to the big, Canadian high-pressure system that rolled in behind yesterday's cold front.

But down at the beaches , in addition to a very noisy Bike (read "Motorcycle") Week in Ocean City, forecasters are looking for clouds and rain as low pressure develops off the Carolina coast.

Counter-clockwise winds around that low will bring the resorts 20 to 40 percent rain chances and a chilly onshore wind of 10, building to 25 mph.

Speaking of cool September weather, the low of 45 degrees at BWI overnight tied with Sept. 16, 2001 as the third-lowest reading on record for the date, going all the way back to 1872, according to the National Weather Service. The lowest was 41 degrees, registered on the same date in 1873.




Posted by Frank Roylance at 11:10 AM | | Comments (1)
Categories: Forecasts

September 15, 2011

Clouds moving in with cold front, rain

Sure, the sun is shining out there this morning, and it's a pleasant 75 degrees or so. But it's not going to last long.

The National Weather Service radar and satellite data clearly show there's a front with much cooler air behind it, poised on Thursday morning just to our west. It comes out of the Ohio Valley with plenty of clouds. And as it moves across Central Maryland later today, there's a 50 percent chance it will announce itself with some showers and thunderstorms.

Forecasters are calling for less than a tenth of an inch of rain with the frontal passage, or more in BWI radarthunderstorms. The colder Canadian air behind it could arrive with gusty winds, and small hail. But it will clear off quickly, and then late-afternoon temperatures will begin to drop into the 50s.

Some locations at higher elevations to our west will fall into the upper 30s tonight. "[For t]he first time in several months the words 'patchy frost' have entered my mind," one NWS forecaster said in this morning's forecast discussion. He doesn't really think there will be frost, though. "Still a touch too warm for frost formation," he said.

But, as we've been saying for days, we are looking at some much cooler weather for the weekend, with highs only in the 60s. Next week looks sunny and warmer, with daytime highs at BWI climbing slowly back toward 80 degrees by mid-week.

Meanwhile, out in the Atlantic, Tropical Storm Maria, with top sustained winds at 65 mph, is passing immediately west of Bermuda. A Hurricane Watch and Tropical Storm Warning are posted for the island. Tropical storm winds and 1 to 3 inches of rain are forecast there. The storm could reach hurricane force briefly before weakening in the next few days, the National Hurricane Center said.

UPDATE, 11 a.m.: Maria now has top winds of 70 mph, just below hurricane force. It is now expected to become a hurricane later today. 

UPDATE, 5:30 p.m.: Maria is now a minimal hurricane, with top winds of 75 mph. It is only the third storm this season to reach hurricane strength. A Hurricane Watch and Tropical Storm Warning have been issued for southeastern Newfoundland as Maria accelerates to the north northeast at 36 mph.

There is a "moderate" rip current risk at the beaches. And the weekend at the shore looks problematic, with east winds, clouds and rain chances both days.

Here is the latest advisory on Maria. Here is the forecast discussion. Here is the forecast storm track.

Posted by Frank Roylance at 10:22 AM | | Comments (0)
Categories: Forecasts

September 14, 2011

Summer's final weekend will top out in 60s

Lots of sunshine, highs in the mid- to upper-80s, and the threat of late-day thunderstorms ... Sure sounds like summer, doesn't it? Well, enjoy it while you can, because today may well be the last Mushroomstruly hot summer day of the year.

After the first of two cold fronts moves through with some showers and storms tonight, daytime temperatures Thursday will hold in the mid-70s. And after a second front rolls by with some storm chances late Thursday into Friday, the real Canadian air will arrive, and our highs will hold in the 60s until Monday. 

Next week looks beautiful, with sunny skies. But temperatures will hold in the 70s. And summer will officially end on Friday, the 23rd.

What we'll all probably notice most will be the chill in the air overnight later this week.

The National Weather Service is predicting lows early Friday morning in the 40s to the west of the I-95 corridor. Higher elevations in Western Maryland could record some lows in the 30s. Closer to the relatively warm Chesapeake Bay, we should hold in the 50s overnight, although the BWI forecast for Thursday night into Friday calls for a low of 48 degrees.

(SUN PHOTO: Frank Roylance. Still looking for an ID on these mushrooms. Anyone?  Can we saute them?)

Posted by Frank Roylance at 10:41 AM | | Comments (4)
Categories: Forecasts

September 13, 2011

A chilly end to the week ahead

We'll have a couple more days in the mid-80s this week. But by Thursday, after a frontal passage Wednesday evening into Thursday that could trigger some showers and storms, the season's first chilly Canadian cold front will bring Central Maryland a taste of autumn. High temperatures from Thursday right through the weekend will struggle to reach 70 degrees.

Air conditioners, at least, will be silenced. But a few of us may be tempted to awaken the heaters as overnight lows drop to the low 50s, and even into the 40s to the north and west of I-95. I see BWI rainfallwe already picked up the season's first two degree-days last Tuesday. The high that rainy day was 64; the low was 62, for an average of 63 degrees. That was 8 degrees below the norm. 

We'll have a bunch more before the week is out. Some parts of the country may see their first frost this week. But not us.

The average highs for Baltimore at this time of year have slipped into the upper 70s. The average lows are now in the 50s. So it really is time for us to have some days like those we'll see by week's end. At the same time, it's still possible for highs to reach the 90s.

Every date in September has a record high of 91 degrees or more. The record for the month isBWI precip 101 degrees, reached on Sept. 7, 1881. 

Finally, I need to acknowledge the beautiful Harvest Moon that rose over Baltimore last evening. Busy as we've been with earthquake, hurricane, Grand Prix and flooding, this one got past me.

The Harvest Moon is defined as the full moon closest to the autumnal equinox. The equinox this year occurs at 5:06 a.m. on Sept. 23. That's 11 days after the September full moon. The next full moon occurs on Oct. 11. That's 18 days after the equinox, so that one's the Hunter's Moon. 

Posted by Frank Roylance at 10:24 AM | | Comments (0)
Categories: Forecasts

September 2, 2011

Rain risk fades for Grand Prix on Saturday

The chances for rain on the Baltimore Grand Prix on Saturday have disappeared. The National Weather Service has dropped the 30 percent rain chances that were in the forecast this morning. Now, they're calling for partly sunny skies and a high of 85 degrees Saturday.

The 30 percent rain risk remains for Sunday, however, mostly after 2 p.m., as a trough of low pressure comes to dominate ahead of an approaching cold front. It will be hot and humid, with highs near 90. And Monday looks like a wet one, cloudy and cooler (80), with 60 percent chances for thunderstorms Monday and Monday night.

Chances for showers and storms continue for the rest of next week at 30 to 40 percent as the stalled cold front drags tropical moisture north with the remnants of Tropical Storm Lee. Forecasters said:




Posted by Frank Roylance at 5:19 PM | | Comments (0)
Categories: Forecasts

Monday looking wetter thanks to Gulf storm

Baltimore Grand Prix fans may see some showers or thunderstorms on Saturday or Sunday. But forecasters have become even more certain that Labor Day Monday will bring significant rain to the region as a low-pressure system begins to draw tropical moisture this way from the Gulf.

Baltimore Grand Prix racing events should will be completed by Sunday. But Monday is scheduled as a make-up day if Saturday or Sunday events are postponed by weather or some other issue. 

The wet weather on Monday will include moisture from what hurricane forecasters expect will become Tropical Storm Lee later on Friday. The slow-moving storm is loitering in the northern Gulf of Grand Prix St. PetersburgMexico, and is forecast to dump as much as 20 inches of rain on portions of the northern Gulf Coast. More on that in the next post.

The National Weather Service's regional forecast office in Sterling, Va. says there's a 30 percent chance for rain at BWI-Marshall Airport on Saturday, with showers and thunderstorms most likely to appear after 2 p.m., just as the main events at the Grand Prix are getting underway. Forecasters expect less than a tenth of an inch of rain, unless you happen to be under a thunderstorm.

Rain chances on Sunday are the same - 30 percent - and so are the expected accumulations and the timing. On Sunday night and Monday, however, the predicted rain chances jump to 60 percent, with "thunderstorms likely."

Later in the week, forecasters expect the region will begin to feel the direct effects of whatever is left of that Gulf Storm:

"Long range models suggest a plume of tropical moisture from what should be named Lee will stream across the mid-Atlantic from the middle of next week into next weekend. This, along with an offshore flow, could create a significant rainfall event for the region, particularly for east-facing ridges, such as the Blue Ridge."

(PHOTO: Mike Ehrman, Getty Images, March 2011)

Posted by Frank Roylance at 10:06 AM | | Comments (0)
Categories: Forecasts

September 1, 2011

Rain chances for Grand Prix at 30 to 40 percent

It's still looking like race fans will see showers or thunderstorms sometime during the three-day Baltimore Grand Prix "Festival of Speed" this weekend.

Grand Prix wet trackThe National Weather Service at Sterling, Va., says an approaching cold front will bring clouds and the threat of rain beginning sometime after 2 p.m. Saturday. It doesn't sound like a gusher of rain - unless a thunderstorm passes right over downtown Baltimore.

But a wet track and wet grandstands could make it an interesting weekend for drivers and fans. The chances are set at 30 percent on Saturday, rising to 40 percent on Sunday and Monday. Don't let the clouds fool you into skipping the sun block.

Once the cold front gets by us on Monday, Central Maryland will be seeing some cooler weather. Lows by Tuesday are forecast to hold in the 70s for only the fifth time since June 1. Same for Wednesday.  

Starting to feel like autumn is just around the corner. But late summer is a beautiful time of year in Maryland. Enjoy it. 

(PHOTO: Grand Prix South Korea 2010. Peter Parks, AFP/Getty Images)

Posted by Frank Roylance at 10:27 AM | | Comments (1)
Categories: Forecasts

August 31, 2011

A wet track for the Baltimore Grand Prix?

At the end of a week of deep blue skies, the folks driving the Indy cars in the Baltimore Grand Prix races this weekend may have to contend with some rain on the track. And those in the stands will need to pack rain gear. 

NHC/NOAAThe forecast from the National Weather Service forecast office in Sterling, Va., say there's a 40 percent chance of showers and thunderstorms on Saturday, with a 30 percent chance through Labor Day Monday. Temperatures, at least, will be ideal, in the low-to-mid 80s. Skies, between the showers, will be partly sunny.

The issue will be a slow-moving cold front that's forecast to approach the region through the weekend. Showers and storms will crop up ahead of the front, which won't clear the area until late Monday, if the predictions from Sterling prove accurate.

The forecast is much the same for Ocean City, except that the front won't begin to affect the weather there with showers and storms until Sunday. So Saturday may be your most reliably sunny day at the beach. 

One other issue in the 7-day forecast this morning is a disturbance in the far western Caribbean. For now, the National Hurricane Center is giving it only a 10 percent chance of becoming the next named tropical storm within the next 48 hours. 

The thinking is that the storm, if it develops, may move to the Gulf Coast and then north along the frontal boundary into the mid-Atlantic by Tuesday. If so, we might see some serious rain by Tuesday or Wednesday next week. "Something to keep an eye on," forecasters said.

The satellite image above shows the Caribbean disturbance near western Cuba. The swirl at the extreme right is Tropical Storm Katia, also on forcasters' worry list this morning.

Posted by Frank Roylance at 10:25 AM | | Comments (0)
Categories: Forecasts

August 26, 2011

Baltimore now under Tropical Storm Warning

Hurricane Irene, packing 110 mph winds, heavy rain and a 4 to 8-foot storm surge, continues to bear down on eastern North Carolina, southeastern Virginia and Maryland this morning. Hurricane Warnings now stretch from North Carolina to New Jersey, including the Maryland and Delaware resorts.

Baltimore and the entire Western Shore of Maryland - and the Eastern Shore inland from the beaches, are under a Tropical Storm Warning. Tropical storm conditions are now expected by Saturday from Baltimore, Howard and Montgomery counties, south and east.Irene severity

The National Weather Service forecast office in Sterling, Va. says winds at BWI-Marshall Airport will pick up Saturday afternoon, with sustained winds increasing to 24 to 29 mph Saturday, gusting to 34. Saturday night, winds will increase to between 37 and 47 mph, gusting to 54 mph.

The Western Shore region should also be prepared for 6 to 8 inches of rain through Sunday, with more to the east. Up to a foot of rain is possible on the Lower Eastern Shore. A Flash Flood Watch was posted for the entire Western Shore. 

A storm surge of 4 to 8 feet was predicted for southern portions of the Chesapeake, its tributaries, the Eastern Shore and Delmarva. The beaches will see large and destructive waves.

"Now is the time to rush to completion preparations for the protection of life and property," forecasters warned. "Evacuate if directed to do so by local officials, or if your home  is vulnerable to high wind or flooding." Here's more:


At the 5 a.m. report, Hurricane Irene was located about 400 miles south of Cape Hatteras, moving north at 14 mph. Top sustained winds had eased a bit to 110 mph. Some restrengthening was possible, and the storm was expected to pass near or over the Outer Banks Saturday, at Cat. 2 or 3.

Here is the forecast for Ocean City. Here is the latest advisory on Irene. Here is the forecast discussion.  

Posted by Frank Roylance at 6:52 AM | | Comments (8)
Categories: Forecasts, Hurricanes

August 24, 2011

Irene forecast track edges eastward

There are plenty of uncertainties still, but hurricane forecasters have nudged their forecast track for Hurricane Irene just a bit more to the east. If that holds up, it could mean this will be more of a coastal storm for the Maryland and Delaware resorts. And for the Western Shore, at least, that NHC Irenewould spare us an Isabel-like storm surge up the Chesapeake Bay.

That's not to say Central Maryland would escape Irene's wrath entirely. We can still probably expect some heavy rain over the weekend. And because we've been getting more rain lately, and are expecting more from a cold front due here on Thursday, weekend rain from Irene will fall on soils and in streams already full of water. And that raises the risks of flooding.

Here's Jeffrey Halverson, associate professor of geography and environmental systems at UMBC, on the rain potential:

"Big storms like Irene, even while along the coast or offshore, can circulate Atlantic moisture inland well in advance of the actual storm center. Moderate to heavy rain may actually begin spreading up the East Coast 24-36 hours ahead of the storm. The models are certainly presenting this scenario."

At 11 a.m., Irene was located about 285 miles southeast of Nassau, moving to the northwest at 12 mph. Top sustained winds were clocked at 115 mph, making Irene a "major," Category 3 hurricane.

Hurricane-force winds were expected in the Central Bahamas by Wednesday night, and in the northwestern Bahamas on Thursday. Storm suges of 7 to 11 feet above normal tide levels are possible in the Bahamas, along with large and dangerous waves. Rainfall could total 6 to 12 inches in the Bahamas.

The center of the National Hurricane Center's "cone of uncertainty" for Irene's future path turns her gradually to the northwest and then north in the next two days. That would take Irene ashore in the Outer Banks region of North Carolina. Mandatory evacuation orders are already up for Okracoke Island.

The current path would place the storm at the mouth of the Chesapeake Bay by 2 a.m. Sunday. Forecasters at the National Weather Service regional forecast office in Sterling, Va., say Irene will arrive there as a coldfront crosses Maryland from the northwest. As the moist tropical air runs up against the cold front, it would trigger heavy rain in Central Maryland.

The impact at the beaches will depend on Irene's strength - it's forecast to be a Cat..1 hurricane at that stage - and how close she comes to the shoreline. But those at the beaches can expected heavy rain, wind and surf. Here's a (clickable) map of the wind forecast for Sunday. It shows strong winds on the Lower Eastern Shore and the lower bay.

The NWS forecast office in Wakefield, Va., is saying that tropical storm conditions are possible for Ocean City Saturday night and Sunday. Here's part of their morning forecast discussion from Wakefield:


Here is the latest forecast advisory for Irene. Here is the forecast track. And here is the National Hurricane Center's forecast discussion.

Posted by Frank Roylance at 11:00 AM | | Comments (12)
Categories: Forecasts, Hurricanes

August 23, 2011

Irene may spoil your weekend

What is it about these storms that begin with the letter "I"? Remember Isabel in 2003?

Well, forecasters at the National Hurricane Center say Hurricane Irene appears to be headed our way this weekend. They stress that track forecasts this far in advance can be off by 200 or 250 miles. But the computer models still seem to be in close agreement about this one.

Irene forecast trackThey're predicting landfall late Saturday or early Sunday somewhere near the North Carolina/ South Carolina border. It would be the first hurricane landfall on the U.S. mainland since 2008.

From there, Irene seems likely to continue moving north.

Her track after landfall will be of critical importance to Central Maryland and the Eastern Shore. A curve toward the east would put the Baltimore-Washington area on the more benign west side of the storm's center. That would mean less rain and wind, with winds shoving water down the bay.

But a northward track to the west of the Chesapeake Bay could be expected to blow water up the bay, raising the dangers of a large storm surge and destructive coastal flooding. Think of how storms like Hazel in 1954 and Isabel in 2003 producing severe coastal flooding along the bay shores.Floyd rain 1999

UPDATE, 12 noon: The latest National Hurricane Center track forecast still shows Irene approaching the Chesapeake Bay by daybreak Sunday. The center of the "cone of uncertainty" puts the storm at the mouth of the Chesapeake - still at Cat. 1 hurricane strength - by 8 a.m.

At noon Tuesday, Irene was a Cat. 2 hurricane, packing top sustained winds of 100 mph. It was located about 70 miles south of Grand Turk Island in the Bahamas, moving to the west northwest at 12 mph. Forecasters said Irene could reach Cat. 4, with sustained winds above 131 mph, by early Friday morning. It is thought likely to be a Cat. 3 storm at landfall in North Carolina early Sunday morning. 

Earlier post resumes below.

The official forecast doesn't sound too dire. The NWS/Sterling is calling for highs in the low 80s, with the chances for showers and thunderstorms rising from 50 percent Saturday to 60 percent Saturday night. The probabilities slip to 40 percent Sunday and Monday.

Here's's take on the storm. says Irene's forecast track looks most like Hurricane Bertha, which struck near Wilmington, N.C. in July 1996 and caused tremendous damage along the nearby beach communities of Wrightsville and Topsail Beach. Twelve people died and property damage was estimated at $270 million.

In Maryland, a much-weakened Bertha delivered plenty of rain and wind, and caused widespread power outages. But there was little serious damage, even at Ocean City.

Hurricane Floyd, in 1999, also followed a path similar to that forecast for Irene. It dropped 14 inches of rain on portions of Maryland, and produced winds of 50 to 70 mph. There was a 2 to 3-foot storm surge in the bay. Three Marylanders died and 250,000 lost electric power.

Isabel's path was quite different. It made landfall in North Carolina and drove inland toward West Virginia. Rainfall in Baltimore was not extraordinary, but the counter-clockwise winds around the storm's center drove water up the bay, causing some record storm surge numbers, with tremendous damage around the Inner Harbor, Fells Point and other bayshore communities such as Bowley's Quarters.

Here is the latest advisory on Irene. Here is the forecast discussion.

There's more below from Prof. Jeffrey Halverson, Associate Professor of Geography and Environmental Systems at UMBC

(Top: NWS, Irene forecast track. Bottom: Floyd, 1999)  

Continue reading "Irene may spoil your weekend" »

Posted by Frank Roylance at 10:43 AM | | Comments (8)
Categories: Forecasts, Hurricanes

August 22, 2011

Dry, breezy and sunny until ...

Sunday's storms marked the passage of the cold front that has brought us this bright, sunny and dry weather for the bulk of this week.

The high-pressure system pushing in on north winds will mean very pleasant weather for the mid-Atlantic through Thursday morning. Chances for some showers and thunderstorms return Thursday afternoon with the next cold front, and those chances will grow through the weekend as Hurricane Irene approaches.

NHC/NOAAThe National Weather Service regional forecast office in Sterling is predicting highs in the low 80s Monday and Tuesday. In between, overnight lows may dip into the 50s Tuesday morning, and the 60s in the cities. By Tuesday night, Wednesday morning, we could record some lows in the 50s in the urban corridor, too.

In the meantime, forecasters along the East Coast are watching the progress of Hurricane Irene. Some additional weather balloons will be launched this afternoon at Sterling to support the effort. For now, here's what the local forecasters are saying:

"With most of the medium to long-range  guidance taking Irene roughly up the Atlantic coast from the Florida peninsula to New England, will watch the progress and trends in the coming days. Irene, according to latest runs of these models, may affect the easternmnost sections of the [forecast area] Sunday into Monday of the coming weekend, early next week.

"The synoptic pattern over the Great Lakes, New England under this type of scenario would give the tropical system a bit of an opening to make this northerly trek up the coast..." is predicting landfall Saturday night in the Carolinas.

Word to the wise: If your sump pump is ailing, or your storm drains are clogged, this week will be a great time to get them fixed and ready to flow.

Posted by Frank Roylance at 11:55 AM | | Comments (4)
Categories: Forecasts

Hurricane Irene poised for sweep up the East Coast

The first hurricane of the 2011 Atlantic season was leaving Puerto Rico and moving toward the AccuWeather.comnorthern coast of the Dominican Republic and Haiti Monday morning.

And if Hurricane Irene follows the forecast storm track, it can be expected to steer a bit more to the north later this week and threaten the east coast of Florida, Georgia and the Carolinas. Miami forecasters are predicting tropical storm conditions there by Thursday. is forecasting landfall late Saturday in the Carolinas.

And at least one forecast model is predicting a very heavy rain/wind/surf event for the mid-Atlantic coast early next week. 

Top sustained winds at Irene's center were blowing at 80 mph, making this a mid-range Category 1 hurricane for now. But some further strengthening is expected in the next few days.

NHC/NOAAHurricane Warnings have been dropped for Puerto Rico and nearby islands, replaced by Tropical Storm Warnings.

Hurricane Warnings have been posted for the north coast of Hispaniola. Hurricane Watches are up for the south coast of the Dominican Republic and Haiti. Tropical Storm Warnings are in place for Puerto Rico, the U.S. and British Virgin Islands, all of Haiti and the south coast of the Dominican Republic, as well as the southeastern Bahamas and the Turks and Caicos Islands.

Five to 10 inches of rain are possible in Puerto Rico, the Virgin Islands and Hispaniola as Irene blows by. As much as 20 inches are possible in some locations. Storm surges of 1 to 4 feet are expected, with large and dangerous waves.

Irene forecastThe National Hurricane Center is watching the atmosphere to Irene's north, where high pressure is keeping the storm from curving north into the open Atlantic. Instead, it is being steered west, closer to the U.S. coast.

Computer models differ on how close to the coast the storm will get. But there does appear to be some agreement that it will continue to strengthen. The forecast discussion says:


Here is the latest advisory for Irene. Here is the forecast track. Here is the forecast discussion.

Jeffrey B. Halverson, associate professor of geography and environmental systems at UMBC, is watching Irene's progress. He sent the latest GFS model results (for Monday, left). He said:

"For three days now, it has been portending a significant heavy rain event for the Mid Atlantic, and wind/high surf along the Eastern Shore. The track, heavy rain footprint and slow speed of the storm through the Mid Atlantic continues to look very Agnes (1972)-like."'s Alex Sasnowski, said, "It is very possible strong tropical storm or even hurricane conditions will continue to spread up the Atlantic Seaboard.

"If the fats forward motion of the storm continues, it could spread damage, including that of downed trees, power lines and coatal flooding issues, into the mid-Atlantic late this weekend and into southern and eastern New England by early next week."

Posted by Frank Roylance at 9:35 AM | | Comments (1)
Categories: Forecasts, Hurricanes

August 18, 2011

Rain risk continues through Monday

With warm, humid winds continuing to flow out of the south and southeast, Central Maryland is expected to remain in a period of persistent rain threats through Monday, as a series of Rain chances Fridaydisturbances set off scattered showers and storms. The best chances are focused on the period from tonight through Friday.

The National Weather Service regional forecast office in Sterling, Va. says Thursday will be the hottest day of the period, with forecast highs near 90. Rain chances are put at 40 percent today, rising to 50 percent tonight and 60 percent on Friday (map).  As much as a quarter inch is possible Friday, with more in thunderstorms.

So we can look forward to periods of sunshine, followed by showers and storms, most likely in the afternoon and evening. Some may produce localized heavy rain and flash flooding. Daytime highs will be in the upper 80s at BWI-Marshall Airport.

The next cold front, arriving late Sunday into Monday, should clear the air and deliver a couple of days of sunny skies and seasonable temperatures.

In the meantime, Central Maryland is under a Code Orange Air Quality Alert through Thursday. So breathe as little as possible if you go outdoors. 

Recent rains have sharply reduced the percentage of Maryland experiencing "Moderate" drought conditions, from 84 percent to just under 18 percent, according to the new Drought Monitor Map released this morning. But the portion still rated as "Abnormally dry," which includes the Baltimore metro area, was put at 91 percent, down only slightly from last week's 95 percent. 

Posted by Frank Roylance at 10:40 AM | | Comments (0)
Categories: Forecasts

August 17, 2011

More rain due for Thursday, Friday

Looks like Central Maryland can expect some more beneficial rain in the next couple of days. Forecasters at the National Weather Service in Sterling, Va. say that, after a fine, warm, sunny and seasonable day on Wednesday, the first in a pair of cold fronts will pass through with a 40 percent chance of showers and storms.

BWI rainfall AugustThe first sign of a change in the weather will likely be some increasing cloudiness. As the high that's bringing today's pleasant weather moves off the coast, the wind will shift more to the south, bringing more moisture up from the Atlantic, off the Carolina coast.

Overnight, or by Thursday - the computer models disagree - the first cold front will approach from the Ohio Valley, setting off some showers and storms by Thursday afternoon. A quarter- to a half-inch is possible Thursday, with another quarter-inch to follow overnight into Friday. Ditto for Friday and Friday night. The garden will be happy.

The weekend looks terrific as the low departs and high pressure builds in behind it. Look for sunny skies, lower humidity and temperatures in the mid-80s.

By Monday, forecasters say we'll be looking at the next cold front, which is likely to be more potent than this week's, with a 40 percent chance for more rain. Sunshine returns by Tuesday, with a high for Baltimore of just 80 degrees. This is the weather we were wishing for last month.

Posted by Frank Roylance at 11:06 AM | | Comments (0)
Categories: Forecasts

August 15, 2011

More showers and storms ahead

The barrage of showers and thunderstorms we've been seeing for the last couple of days seems likely to continue Monday and Tuesday. But forecasters at the National Weather Service expect the atmosphere will be drying out some, allowing the storms to diminish. Wednesday and Thursday should be mostly rain-free.

Coastal low Blame a low-pressure system that moved slowly out of the Ohio Valley over the weekend. The counter-clockwise spin around the low picked up moisture from an unusually warm Atlantic Ocean and sent a plume of moisture-laden air north. There it ran up onto the mid-Atlantic states, dropping heavy rains that added up totals equal to a month or two of normal precipitation in some spots.

The storm center is moving up the East Coast today, but very slowly. That will leave us to deal with some additional showers and storms this afternoon, tonight and Tuesday. Flash flooding, such as that which submerged cars on Patapsco Avenue and flooded basements in Cherry Hill this morning, also remains a possibility. A Flash Flood Watch is in effect for Baltimore and its suburbs until 8 p.m. Monday. 

But drier air will continue to move our way, gradually easing us toward a sunny, dry day on Wednesday, and again of Thursday. By then, the high pressure that follows this stormy low, will have moved east, putting us once agaion in the return flow, forecasters said. Heat and humidity will rise again, and rain chances will be back for late Thursday, Friday and Saturday.

Posted by Frank Roylance at 12:50 PM | | Comments (0)
Categories: Forecasts

Showers and storms drop big rain ... for some

Just in, finally, from a pleasant hour on the JFX, watching the rain fall and trickle down the gutter beside the "fast" lane. The mid-morning thunderstorm toppled a tree across all three southbound lanes, just north of the Druid Park Lake Drive exit. Traffic had backed up to just below Cold Spring by the time I arrived. From there to the tree took about an hour. But I had plenty of company. Were you there, too?

The heavy rain caused loads of problems, elsewhere, too. Click here for more

I was out of town for the weekend, but it's clear from this morning's CoCoRaHS Network report that some locations across the region had some huge rainfall numbers. BWI-Marshall Airport was not among them. Although the airport got a nice rinse, the weekend total was just just 1.5 inches. Parts of the Eastern Shore, where the drought has been the most severe this summer, saw a month or more of rain:Lightning


Bishopville, Worcester County: 4.99 inches

Ocean City:  4.40 inches 

White Oak, Montgomery:  3.52 inches

Kingsville, Harford:  3.22 inches

Baltimore City:  3.21 inches

Catonsville, Baltimore County:  2.83 inches

Towson, Baltimore County:  2.29 inches

Bel Air, Harford:  1.92 inches

Columbia, Howard:  1.10 inches

Westminster, Carroll:  0.73 inch


White Marsh, Baltimore County:  3.92 inches

North East, Cecil:  3.85 inches

Waldorf, Charles:  2.30 inches

Annapolis, Anne Arundel: 2.23 inches

Baltimore City:  1.52 inches

Cockeysville, Baltimore County:  1.15 inches

Columbia, Howard:  0.78 inch

Salisbury, Wicomico:  0.62 inch

(PHOTO: Top: James Willinghan, Howard County, Aug. 14, 2011. Used with permission. Bottom: Frank Roylance, Baltimore Sun)


Posted by Frank Roylance at 11:49 AM | | Comments (2)
Categories: Flooding, Forecasts

August 11, 2011

Beautiful end to week, beneficial rain by Sunday

It's hard to find anything NOT to like in the seven-day NWS forecast this morning. We're in line for a couple of beautiful summer days Thursday and Friday. And by late Saturday and Sunday, forecasters are calling for some badly needed rain.

And there are no more 90-degree days anywhere in the forecast through next Wednesday. Maybe it's payback for July. With Wednesday's BWI high of 90 degrees, the season's total stands at 40 days of 90-plus weather. The record is 59, set last year.

We start the 7-day predictions with two gorgeous days in the mid-80s, with loads of sunshine Thursday and Friday, and low humidity. The sky on the drive in this morning was as blue as it's been all summer. We can thank the Canadians for this one.

MushroomLow pressure over Northern Quebec and high pressure over the Midwest are combining to draw cool, dry air down from Canada, clearing our air of both heat and humidity. BWI-Marshall Airport could see an overnight low of just 60 degrees tonight. 

As the high moves our way and on to the east on late on Friday, we'll start to see some increasing clouds, humidity and rising temperatures as winds shift from north to south. And by late Saturday into Sunday, forecasters say we'll begin to get some thunderstorms.

"Best chance in some time for much needed rainfall," the folks at Sterling said in this morning's forecast discussion. "Despite very dry antecedent conditions, heavy rain in short duration brings risk of localized flash flooding, particularly in urban areas and where thunderstorms train."

All this comes ahead of the next cold front. Once that goes by on Sunday, rain chances will slowly diminish, though with some rain chances remaining into Monday. But temperatures will drop below the seasonal norms, to the low 80s and the new workweek begins.

Whatever rain we get  will be welcome. The new Drought Monitor map out this morning shows no change in the extent of drought conditions across the state. Moisture remains normal in less than 5 percent of the state. "Abnormally dry" conditions or worse persist in the rest, with 84 percent of the state, including Baltimore and its suburbs,  in "moderate drought." Another 5 percent, centered on Wicomico County on the Lower Eastern Shore, remains in "Severe Drought."

(SUN PHOTO: Mushroom, Frank Roylance, 2011) 

Posted by Frank Roylance at 10:08 AM | | Comments (1)
Categories: Forecasts

August 10, 2011

Cooler, drier weather on tap

Temperatures across Central Maryland will run below normal for the next couple of days as a cold front clears the air. The front will pass through late today, reinforcing the one that swept past last Mushroomevening with some welcome showers. This time the frontal passage will be dry.

Behind the front, forecasters say we'll enjoy lower humidity as dew points drop into the mid-50s. Daytime highs for Thursday and Friday will hold in the low 80s. Overnight lows will fall to the upper 50s in the western counties to the mid- to upper-60s in the urban and suburban counties. So switch off the AC tonight and open the windows.

But first, we'll have to deal with one more day of near-90-degree weather. Thankfully, humidities are already decreasing, so even 90 degrees will feel pretty comfortable today (Wednesday).

By late Friday, however, the high pressure center that is bringing us this pleasant interlude will move off the coast. That brings us into the return flow, with winds shifting to the south or southeast. And that will bring us a shot of warmer, more humid air off the Gulf and the Atlantic, and increasing clouds for the weekend.

We should expect that will increase our chances for showers and thunderstorms for the weekend. Forecasters give us a 60 percent chance for storms Saturday night, 40 percent on Sunday and 30 percent on Monday. With all the clouds to shade us, daily highs won't change much, remaining in the near-normal mid-80s well into next week.

Recent rains have brought forth a half-fairy-circle of these mushrooms near the WeatherDeck in Cockeysville. Can anyone identify the species?

(SUN PHOTO: Frank Roylance, Aug. 9, 2011)

Posted by Frank Roylance at 10:24 AM | | Comments (3)
Categories: Forecasts

August 8, 2011

Below-normal temps by 2nd half of the week

Central Maryland could see a few showers and thunderstorms along with 90-degree weather during the next few days as a series of cold fronts approach, and pass through the area. But beyond Wednesday, skies should clear behind the last of the fronts, and our average temperatures will drop just below the long-term averages.BWI Temperatures

We've seen few below-average days this summer. We enjoyed a couple on the 4th and 5th last week. The days' averages were 1 degree below the long-term norms. But before that we have to go back to July 16 to find another "cooler-than-average" day. For the summer-to-date, since June 1, there have been just 13 days that ended cooler than  the long-term averages. We've had just five since July 1.

By Thursday, though, forecasters see the BWI-Marshall Airport high as a mere 84 degrees. And readings should remain in the mid-80s at least through the weekend. The 30-year average high for this time of year in Baltimore is 86 degrees. The beach forecast for the latter half of the week through the weekend looks fabulous.

Any rain we get during the first half of the week will be a bonus. The showers and storms that moved through the region on Sunday were very spotty. We could hear some thunder from the WeatherDeck in Cockeysville, but we never saw a drop. On the other hand, Harford County and points south of Baltimore got a pretty good drink. Here are some totals from the CoCoRaHS Network:

Oxon Hill, PG Co.:  1.22 inchesBWI Precipitation

North Laurel, Howard:  1.02 inches

Havre de Grace, Harford:  0.85 inch

Kingsville, Harford: 0.79 inch

Ellicott City, Howard:  0.49 inch

Baldwin, Baltimore Co.:  0.44 inch

Towson, Baltimore Co.:  0.15 inch

Pasadena, Arundel:  0.12 inch 

And, if anybody's wondering, the tropics look quiet again. The National Hurricane Center last night issued its last advisory on the remnants of Tropical Storm Emily. The storm was located 295 miles south southeast of Cape Hatteras and 555 miles west of Bermuda, moving northeast at 17 mph with top sustained winds of just 30 mph.

There were no watches or warnings anywhere for Emily, and no other storms being monitored.

Posted by Frank Roylance at 11:03 AM | | Comments (0)
Categories: Forecasts

August 5, 2011

Showers, storms this weekend; heat returns

A couple of days of pleasant temperatures and lower humidity will wind up today as the high pressure that brought them moves off the coast. Look for increasing humidity later today and tomorrow, with rising chances for showers and storms, and the return of 90-plus weather for the BWI temperatures Augustweekend and beyond.

The return to hot-and-humid comes as the high moves east, and Central Maryland falls under the return flow on the west side of the clockwise motion of winds around that high. That brings warmer and wetter air from the east southeast. Looks like we'll remain rain-free this afternoon, while rain chances rise in the western counties.

With the moisture will come more clouds overnight, and by Saturday morning our chances for showers and storms climb to 50 to 60 percent for Saturday.  A storm system moving our way from the Plains will reach us by Saturday afternoon, triggering showers, some of which could drop heavy rain, up to a quarter inch in some spots, or more in thunderstorms.

Showers may linger in to Sunday, and temperatures may reach the 90s again. The 90-plus highs will stick around through Wednesday, if forecasters have it right.

Posted by Frank Roylance at 10:50 AM | | Comments (0)
Categories: Forecasts

August 4, 2011

A break in the weather

It looks this morning like the siege of hot and humid weather we've endured for much of the summer is beginning to break up. Forecasters at NWS/Sterling are calling for these mid-80s temperatures to persist for most of the 7-day forecast, with only a quick poke into the low 90s on Sunday.

But we're going to feel the difference. Eric the Red says the jet stream that had deserted us for more northern latitudes for much of the summer, is beginning to take a dive into the eastern third of the nation as the dome of high pressure and torrid temperatures shifts a bit west.

Rain Saturday"This means cooler weather for us, and perhaps some much-needed rain for some folks. The change will start to take place over the weekend, and be in place by early to middle of next week. It will likely still be humid, but daytime highs will be markedly cooler," he said.

The long-term average high for this time of year (using the new 1981-2010 data) is 86 degrees.

The weather service says this morning's clouds and sprinkles - I think I drove through four separate showers on the way into work this morning - will begin to break up this afternoon as the low that brought the showers moves off the coast. 

Friday will find us in some increasingly warm and humid breezes from the south as a warm front pushes this way ahead of a cold front due on Sunday. That will evolve into widespread rain by Friday night and Saturday. With plenty of moisture in the atmosphere, some of us could see what forecasters are describing as "torrential" rains for Saturday, with a quarter- to a half-inch possible. (See rain forecast map for Saturday, above.)

They're less certain about what comes next. But they're predicting highs in the low 90s for Sunday with some additional showers possible. At some point - Sunday or Monday - the cold front will finally get through, and we'll see some cooler and drier weather for early next week. "It will almost feel comfortable, with highs in the 80s and lows in the 60s, and lower dew points," NWS forecasters said in this morning's forecast discussion.

Whatever rain we get is badly needed. The latest Drought Monitor maps, out this morning, show that 84 percent of the state is now in moderate to severe drought. That's a jump from 23 percent last week.

And it does not look like Tropical Storm Emily will get close enough to throw any showers our way. Eric the Red says the same droop in the jet stream that is changing our weather will likely turn Emily away from the mid-Atlantic and out to sea after it cruises north along the Southeast U.S. coast.

"It may still clip Florida, but no way this thing comes up the coast. So that is that," he said.

Posted by Frank Roylance at 10:08 AM | | Comments (1)
Categories: Forecasts

August 3, 2011

Showers and storms, highs in 80s

Thunderstorms overnight were hit-and-miss, but a few areas were hit pretty hard, with toppled trees and downed power lines for some. The shot below was taken this morning in Original Northwood, and sent in by Sun reporter Gus Sentementes:

"This tree on Eastview Road was lopped by the storm last night. I drove along Loch Raven [Boulevard] today and noticed lots of trees with clipped branches. Were we hit by microbursts overnight?" he asked.

I forwarded his question to the NWS forecast office in Sterling, Va. Chris Strong, the Warning Coordination  Meteorologist there, replaied, "I took a look at radar. It was pretty conclusive that a small downburst hit northern Baltimore City." 

Tree damage Aug. 3, 2011There are more showers on tap for mid-day, and increasing risks for more showers and thunderstorms later this afternoon and into the evening. Some, especially in Southern Maryland, could be come severe, with damaging winds and perhaps some isolated tornadoes in the cards, forecasters said.


UPDATE, 2:55 p.m.: BGE says it has restored power to nearly 13,000 customers in the wake of overnight storms. But the company warns that the potential for lightning and gusts to 50 mph in this evening's storms could mean more outages to come later today. "BGE thanks its customers for their patience and understanding," they said. 


Earlier post resumes below.

The overnight storms missed the WeatherDeck in Cockeysville entirely. The largest accumulations were in Baltimore City, Baltimore, Harford and Howard counties. There were some significant totals from Wicomico, too, where it is badly needed.

Here are some totals from the CoCoRaHS Network:

Hamilton (Baltimore City): 0.98 inch

Gwynn Oak,:  0.32 inch

Marriottsville:  0.31 inch

Kingsville:  0.22 inch

Towson:  0.22 inch

The overnight storms knocked out power for more than 14,000 BGE customers. The company website said electric service had been restored for more than 12,000 by 11 a.m.

The rainstorms are part of an approaching low pressure and frontal system. By early Thursday the low will have moved offshore, opening the door to high pressure, clearing skies, seasonable temperatures and drier air through Friday.

But then things will warm into the low 90s again for the weekend, with increasing humidity as the next cold front approaches, higher risks for showers and storms. By Monday, the front will have cleared the region, and we'll be in line for more sunny and hot weather early next week.

(SUN PHOTO: Gus Sentementes)

Posted by Frank Roylance at 10:45 AM | | Comments (0)
Categories: Forecasts

August 2, 2011

90s streak could end Wednesday

The long, long stretch of 90-degree weather Central Maryland has endured since July 17 looks like it will come to an end Wednesday. National Weather Service forecasters in Sterling, VA. are predicting a high Wednesday of just 85 degrees at BWI-Marshall Airport.

BWI temperatures July That would cap the streak at 17 days, including Tuesday, the third-longest consecutive string of 90-degree weather for Baltimore since record-keeping began. In all, July delivered 24 days with 90-plus weather, a record for any month in Baltimore.

After another high Tuesday near 95 degrees, with lower humidity, relief will come to us Wednesday in the form of a "potent" low-pressure system and a cold front. It's expected to reach the area after sunset Tuesday, and should deliver some significant rainfall on Wednesday.

The weather service puts the rain chances Wednesday at 50 percent, with as much as a quarter inch possible. Higher totals are possible in thunderstorms. A few isolated storms could be strong to severe, forecasters said.

Daytime highs will remain in the upper 80s through Saturday, if the forecasters have it right.  The 90s could return to the forecast by Sunday, and more showers and storms are possible during the weekend as the next cold front approaches.

Last night's storms brought plenty of thunder, but widely variable amounts of rain to the region. Here are some representative totals from the CoCoRaHS Network:

Havre de Grace:  1.66 inches

Salisbury:  1.17 inches

College Park:  0.81 inch

Easton:  0.55 inch

Baltimore City:  0.38 inch

Sykesville:  0.35 inch

Jacksonville:  0.35 inch

Towson:  0.22 inch

Pasadena:  0.20 inch

Columbia:  0.10 inch

Posted by Frank Roylance at 10:00 AM | | Comments (5)
Categories: Forecasts, Heat waves

July 29, 2011

Bake-off resumes: Mercury headed for record 101

Forecasters say the mercury is headed for at least 101 degrees this afternoon, both downtown and at the airport. That would make it the 13th consecutive day in the 90s or above, and the fifth day this summer that has reached 100 degrees or more at BWI-Marshall Airport.

It was already 94 at BWI at 11 a.m.

Fortunately, the air is expected to dry out a little by this afternoon, easing the humidity. But the AccuWeather.comweather service still predicts Heat Index values of 105 to 109 degrees.

Here are some milestones to watch for:

1. The record high temperature for Baltimore on a July 29 is 99 degrees, set in 1954. It's one of only four remaining dates in July with a record high of less than 100 degrees. So we seem destined to break that one. Washington and Dulles airports also are forecasted to set new heat records today.

2. The seven-day forecast calls for 90-degree weather through at least next Thursday. Saturday would be the 14th straight day in the 90s or more, matching the third-longest 90-degree streak in Baltimore's weather record book. By next Saturday, if the run persists, we'll match the second-longest streak, at 21 days. The all-time record is 25 days, set in 1995.

The only break in sight comes with a weak cold front, expected to pass through this evening. Some of us may get under a few scattered showers and storms. The best chances are for locations near the Mason-Dixon Line. Any storms that do emerge could produce damaging winds.

Beyond that, there is no rain in the forecast through at least Thursday.

"The region could use ... a good, soaking rain," forecasters said in this morning's discussion. "Unfortunately, this pattern won't be one that can do that. Precipitation will be spotty at best Saturday."

The only good news in the 7-day forecastis that dew points will go down a bit by early next week, "alleviating the mid-Atlantic needing Heat Advisories. But with all the heat the cities [have] stored, low temperatures in Balt/DC will remain in the upper 70s."

Posted by Frank Roylance at 10:39 AM | | Comments (0)
Categories: Forecasts, Heat waves

July 28, 2011

BGE: No plans to trigger Peak Rewards Friday

Temperatures are expected to push into the upper 90s across Central Maryland on Friday. But despite the forecast, BGE says it has no plans to activate its Peak Rewards shutoffs.

Of course, the utility cautions that "unforeseen operating conditions" could change that. They had no plans to activate Peak Rewards last week until grid managers asked them to. So it's a good Friday heatidea, if you're still participating, to make your own plans accordingly.

The forecast calls for a high of 98 at BWI-Marshall Airport, and 99 downtown. Heat Advisories have been issued for all of Central Maryland, and the Lower Shore, with highs potentially reaching the low 100s in some locations, and Heat Index values from 105 to 109 degrees. Two Marylanders died of heat-related causes during Heat Advisories last week.

BGE is urging customers to look for ways to conserve energy on Friday. Keep curtains closed, delay the use of heat-generating appliances until after 9 p.m. To which I would add, if you're vulnerable to the heat, find another, air-conditioned place to go if the utility announces Peak Rewards activation.

"We're extremely sensitive to the discomfort many of our Peak Rewards customers experienced during last Friday's system-wide emergency activation... particularly those who signed up for the highest cycling option and whose air conditioning was off for the duration of the event," said Jeannette Mills, chief BGE customer officer.

The utility is reviewing the program's performance last week, and expects to make any needed changes. Thousands of customers were without their AC for six to eight hours, and 2,500 subsequently quit the Peak Rewards program.

In other news related to the hot-weather forecast for Friday and Saturday, the Baltimore Health Department has already declared Code Red Heat Alerts for the city on both days, opening emergency cooling centers and sending workers out to check on vulnerable residents.

The Maryland State Highway Administration is advising motorists to prepare for the heat by making routine checks of their vehicles - hoses, belts, tires and fluid levels are good places to start. You don't want to be stranded out in the heat by a breakdown.

Park in shaded areas where possible. Remember to take your pets and children with you after you park your car. And bring plenty of water, just in case. And consider public transportation where you can.

Posted by Frank Roylance at 2:58 PM | | Comments (6)
Categories: Forecasts

90s continue, dry conditions spread in Md.

Forecasters are giving us a 20 to 30 percent chance of seeing some showers sometime on Thursday, Friday or Saturday afternoon. The cloud cover that comes with these little disturbances will keep afternoon temperatures from reaching the triple-digit heights that had been forecast for downtown Baltimore on Friday.

But it will remain hot, and increasingly humid. The forecast high for Friday at BWI-Marshall Airport is now 98 degrees, with Heat Index values reaching 104 degrees. Downtown Baltimore could reach 99 degrees Friday afternoon, with humidity pushing the Heat Index to 106 degrees.

And the 90-degree weather is forecast to continue at least through next Wednesday. On Saturday, the streak will reach 14 days. That will tie the mark for the third-longest stretch of 90-plus weather in Baltimore. If we go another week, to next Saturday, the count will stand at 21 days, equal to the second-longest streak of 90-degree weather on record here, set in 1988.

The streak would have to continue until Aug. 10 to match the all-time record for consecutive 90-degree days, 25, in 1995.

In the meantime, dry conditions have spread across Maryland in the past week. The USDA Drought Monitor map released this morning shows all of Maryland except the western two-thirds of Garrett County - almost 94 percent of the state - rated as at least "abnormally dry." That's up from 86 percent last week.

Severe drought remains limited to Wicomico and slices of Worcester and northern Somerset counties on the Lower Eastern Shore - just 5 percent of the state, and unchanged from last week. But "moderate" drought conditions remain south of Easton on the Eastern Shore, and in the southern portions of Calvert and St. Mary's counties, roughly 18 percent of the state.

Posted by Frank Roylance at 10:03 AM | | Comments (1)
Categories: Drought, Forecasts

July 27, 2011

NWS dials back Friday heat forecast, a bit

The official forecast for downtown Baltimore on Friday doesn't look quite so much like a repeat of last Friday. But you probably won't notice the difference.

The National Weather Service has dialed back yesterday's 100-degree prediction for Friday and replaced it with (drumroll) a 99-degree forecast. Temperatures should only reach 97 degrees at BWI Marshall Airport, if the forecasters have it right. And that doesn't sound much worse than BWI tempsTuesday's official BWI high of 95 degrees. 

The fly in the ointment is that after we enjoy a little more of this refreshingly dry heat today, the high that brought it will shift to the east. And that will open the door to the return flow from the south, with all the heat and humidity we've come to know and love this summer.

So it will be 97 or 99 degrees, but with high dew points - a high sweat index. Forecasters are anticipating having to issue some Heat Advisories for Friday and Saturday, as Heat Index values rise to 105 degrees again, increasing the risks of heat-related illness and deaths.BWI rainfall

There appears to be little chance we'll get any beneficial rains over the next week. Forecasters at NWS/Sterling said:

"It is always difficult at this time of year to express any level of confidence with precipitation forecasting multiple days in advance. I've noticed that some trees/leaves are beginning to look stressed from this period of low precipitation and high heat. But unfortunately no widespread soaking rain on the horizon. I'll stick with the 20 to 30 percent probability of precipitation we are  currently forecasting [for Friday], but my confidence is not high that mid-Atlantic will see much rainfall."

The forecast high at BWI today (Wednesday) is 90 degrees. If we make it, that will mark the 11th straight day with highs of 90 or more. The official forecast calls for six more through Tuesday, for a (potential) string of 17.

Posted by Frank Roylance at 10:30 AM | | Comments (0)
Categories: Forecasts

July 26, 2011

Another Friday with 100-degree weather ahead

The temperature is not likely to soar to 108 degrees like it did last Friday, but forecasters are predicting another hot-and-humid Friday ahead with highs reaching 100 degrees in Baltimore. The airport forecast calls for a high of 99 degrees.

For the moment, we're enjoying northerly breezes and low dew points. And while temperatures are expected to pop back into the low 90s today, that's only a few degrees above the 87-degree norm for this time of year at BWI. And the low humidity will keep it relatively comfortable in Central Maryland.

Overnight lows will drop to the upper 60s or low 70s tonight. Wednesday will bring more of the same, with slightly lower afternoon highs.

But all good things must come to an end. In this case, it means the high that took over after a cold front passed through with some showers Monday, will be moving east AccuWeather.comand off the coast by Thursday. That will bring us into the return flow on the backside of the high. And in a repeat of last week's weather, those southerly winds will bring in increasing heat and humidity, while subsidence of the air in the high pressure will heat us up even more.

Forecast highs for the airport jump from 94 degrees on Thursday to 99 on Friday, and to 100 degrees on Friday downtown.

If that sounds faintly comforting given last Friday's unprecedented heat, consider this: At this time last week, the NWS was forecasting a Friday high of 100 at BWI. The actual temperature reached 106 degrees.

So far this summer (through Monday), we have recorded four days of 100 degrees or more at BWI-Marshall Airport, and 28 days of 90-plus weather. The average annual number of 90-plus days at BWI is 29, so by Wednesday we will have tied the annual average.

The 7-day forecast calls for seven more 90-plus days through next Monday, bringing the total to 35 days. Today should be the 12th-straight day at 90 and above, with seven more to come, if forecasters are right.

Anyone for lowering the "heat ceiling?"

Posted by Frank Roylance at 10:23 AM | | Comments (0)
Categories: Forecasts

July 25, 2011

Another week in the 90s ahead

Forecasters are calling for another week of ... well, July weather ahead. They're expecting some showers and thunderstorms Monday and Monday night as a "cold" front pushes through. It's really more of a less-hot front. But after last week's foray into the 100s, it sound just fine to me.

Forecast highs will start the week in the low 90s, with somewhat drier air (dew points in the 50s and Summer shower60s), and gradually push into the mid-90s, with sunny skies and rising humidity, as the week rolls by. The average highs for BWI at this time of year are closer to 87 degrees, so we remain on the hot side. But no one seems to be looking for more triple-digit weather for now.

Any storms we see today and tonight are not likely to become severe. But with so much moisture in the atmosphere, we could be looking at some heavy downpours from slow-moving thunderstorms, forecasters said. Rain chances are put at 70 percent this afternoon and 60 percent tonight.

Once the front goes by, we can look forward to overnight lows dropping into the much more comfortable 60s for the next two nights (70s downtown). We may even be able to open the windows as listen to the cicadas.

As the high begins to move off the coast late in the week, daytime temperatures will climb back into the mid-90s, with rising humidity. We will likely be talking about Heat Advisories and the Heat Index again by Thursday or Friday, as the numbers poke back into the low-100s.

The next break is likely with a new cold front on Sunday.

(SUN PHOTO: Summer storm clears the pool. Karl Merton Ferron, 2000)

Posted by Frank Roylance at 10:01 AM | | Comments (0)
Categories: Forecasts

July 22, 2011

Hot start to a record-breaking day

Here's the rundown on temperatures and Heat Indices for the region at 10 a.m.:

BWI:  Temperature 96 degrees + dew point 76 degrees = Heat Index 109 degrees

Md. Science Center:  Temperature 97 + dew point 76 = Heat Index 111 degrees.

The Sun:  Temperature 97 degrees + dew point (not real reliable) 84 degrees = Heat Index 132 degrees.

PJM InterconnectionI don't think there's much doubt that BWI will be setting a new daily heat record for Baltimore today. The hottest July 22 on the books for Baltimore reached 101 degrees, in 1957. We're just 5 degrees short of that mark at 10 a.m. and there's no rain in sight today. So I'd bet we will knock that record down this afternoon.

The official forecast high for today is 105 degrees downtown, and 103 at the airport

Speaking of records, the PJM Interconnection - the regional power grid that includes Maryland and parts of 12 other states plus the District of Columbia - reported this morning that the region set a new record Thursday for power consumption. We soaked up 158,450 megawatts of electricity. One megawatt is enough to power about 1,000 homes.

The previous record was set Aug. 2, 2006. After some adjustments for changes in the grid since then, PJM estimates the 2006 peak would have been 158,258 megawatts.

The demand for power to keep things cool across the region was met "without problems," the agency said. "Our efforts in fine-tuning how we forecast electricity demand and plan transmission improvements are paying big dividends for our system operations," said Michael Kormos, senior VP for operations.

(PHOTOT: Vicki Valerio, Philadelphia Inquirer, 2003)

Posted by Frank Roylance at 10:17 AM | | Comments (2)
Categories: By the numbers, Forecasts

July 20, 2011

Place to be: Garrett or Allegany counties

Hard to find a pleasant forecast anywhere in Maryland today. There are Excessive Heat and Air Quality alerts up for the entire state on Thursday. Almost, anyway. If you head west, to Garrett or Allegany counties, you'll find the only alert-free zone in the Land of Pleasant Living.

The forecast for McHenry calls for a high today of 86 degrees, with lots of sunshine. The rest of the week looks pretty much the same, with just one poke higher to 90 degrees on Thursday. 

Friday heatFor the rest of us ... Ick. The National Weather Service is calling for a high of 94 degrees at BWI-Marshall Airport today, with a Heat Index expected to reach 102 degrees. Add to that a Code Orange Air Quality Alert. That means toxic pollutants will likely rise to levels considered unhealthy for sensitive groups. Again.

And this will be the best day of the next three. The Excessive Heat Watch takes effect Thursday afternoon for all of Maryland east of Allegany County, including the Eastern Shore. It warns of high temperatures in the upper 90s to 100 degrees, and Heat Index values as high as 111 degrees.

There's a small (20 percent) chance for isolated showers and thunderstorms this afternoon. That might cool some of us down briefly. The chances of a shower continue into the early evening.

No chances on the boards for a shower on Thursday, as forecast temperatures rise to 99 degrees for BWI, and Heat Index values go to 109 degrees.

Friday's predicted high at the airport is 100 degrees (map), with a 30 percent chance of some scattered showers and storms. Saturday looks hot, too, with a high of 100 before the forecast highs drop back into the 90s on Sunday, and the 80s by Tuesday.

Posted by Frank Roylance at 10:26 AM | | Comments (2)
Categories: Forecasts

July 19, 2011

Friday forecast: 100 at BWI, 102 downtown

The National Weather Service has dialed back its predictions for Friday's high temperature at BWI-Marshall Airport - from 102 to a mere 100 degrees. But the high at the Inner Harbor is still forecast to reach 102.

UPDATE, 12:15 p.m.: An Excessive Heat Watch has been posted for Thursday across all of Central and Southern Maryland. Temperatures will be in the upper 90s to 100 degrees, with Heat Index values of 105 to 110 degrees: 


Earlier post resumes: We should expect these predictions to fluctuate as the week goes by, and computer models crunch fresh data and regularly spit out new information. A lot depends on how much cloud cover drifts into the region from elsewhere, providing some feeble shade against the July sun. That's pretty difficult to predict with much precision this far out.

Anyway, in the short term, forecasters are predicting some small chances for showers and thunderstorms Tuesday and Wednesday afternoon - in the range of 20 to 40 percent - as storms Dew Points Fridayfire up in the Midwest and ride around the edge of the high and stagger into Maryland's heat and very high humidity. 

NWS/Sterling science officer Steve Zubrick told me yesterday that dew points during this period will reach the low 70s, with some near the bay sloshing up to 75 degrees or higher. (see map) Add forecast temperatures of 95 again today, 98 on Thursday, 100 Friday and 99 Saturday, and it's going to be stifling.

Heat Index readings - a measure of the combined effects of heat and humidity on the body's ability to cool itself - are expected to top 110 degrees by the end of the week.

The Baltimore Health Department issued a Code Red Heat Alert today, effective through Sunday. That will open cooling centers across the city and send workers out to check on vulnerable residents.

Ocean City looks better, with a predicted high of only 88 degrees for FRiday, rising to 91 by Sunday. Deep Creek Lake is looking forward to highs of 87 for the entire weekend, with chances for showers every day from now thorugh Sunday.

I remember arriving at BWI once on a day like these, stepping out of the air-conditioned baggage claim area into the heat and humidity en route to the parking lots, and thinking, "This can't be the real air; it's gotta be bus exhaust. Nobody can be expected to breathe this stuff."Flower  

Well, it's possible to get a lungful of bus exhaust under there, but it really was the regular air, what Marylanders and visitors alike are expected to breathe in mid-summer. Here's a flower for the grave of whoever invented air conditioning. 

(SUN PHOTO: Amy Davis, 2011)

Posted by Frank Roylance at 10:20 AM | | Comments (1)
Categories: Forecasts

July 18, 2011

Maryland heads into the fryer this week

Hope you enjoyed the seasonable temperatures and low humidity over the weekend, because we are so done with that now.

Forecasters say Marylanders will be seeing temperatures and humidity rising all week, threatening Hotthe 100-degree mark by Thursday afternoon and topping it on Friday. We can count on another string of bad air days, too. Maryland west of the bay and east of Hagerstown is already under a Code Orange Air Quality alert today, meaning air pollution is expected to reach levels considered unhealthy for sensitive groups.

"This is genuinely hot air coming, with dew points somewhere around 70 degrees. Excessive heat watches may be needed by midweek," National Weather Service forecasters said in today's morning weather discussion.

And why not? On average, this is the hottest week of the year for Baltimore. The average daily high is 88 degrees. Daily record highs are all above 100 degrees from the 14th until the 29th, when we see our first record drop back to 99 degrees.Heat wave

The culprit is our old summer friend, the Bermuda High. High pressure centered off the Atlantic coast by Wednesday spins clockwise, pumping hot, humid air our way from the Gulf of Mexico.

But first, we're looking at a forecast high for BWI-Marshall Airport today of 94 degrees. A cold front to our north is bringing some showers and thunderstorms to Pennsylvania later today, and we may see some clouds drift in from that later today. By tonight, showers and thunderstorms could reach communities in the northern and northeastern sections of Sterling's forecast area. Some could become severe, posing risks of flash flooding in the urban corridor. But the computers can't agree on the exact timing or severity of the storms. We don't need severe weather but we can sure suse the rain. 

The weak cold front will deliver slightly cooler air for Tuesday, with a forecast high of 91 degrees and some lingering chance for showers at BWI. But that's just the starting point for steadily rising temperatures and humidity throughout the week and into the weekend.

The forecast calls for temperatures to reach 92 again Wednesday, then pop into the upper 90s to near 100 degrees Thursday and Friday before slipping back to 97 on Sunday. There's a small chance for some showers Sunday, too.

A high of 102 on Friday would break the Baltimore record for the date - 101 degrees, set in 1957.

Anyone ready for November?

Posted by Frank Roylance at 10:18 AM | | Comments (5)
Categories: Forecasts, Heat waves

July 15, 2011

Great weekend to be outdoors

Planning to work on that roof job this weekend? Polishing the car? Caulking the windows? You've picked a great weekend for it. Not too hot ... highs in the mid- to upper-80s, which is about the norm for Baltimore at this time year. And there's no rain in sight.

HammockYou'll need plenty of sunblock, of course. And a hat. The sun angles are still close to the year's maximum. And it's pretty dry, so you'll need lots of fluids to keep you well-hydrated.

And get started early. Conditions will be evolving all weekend, with the high-pressure system that's planted right on top of us today (Friday) moving slowly eastward through the weekend. That means we'll be coming into the return flow around the backside of the clockwise-spinning high. Winds will out of the south and southwest will become increasingly warm and humid.

After rising into the high 80s by Sunday, the mercury will keep on rising into the 90s early next week, forecasters say. We could hit 95 degrees again by Wednesday and Thursday. The only rain in the long-term forecast comes Tuesday with the arrival of another frontal system. There's a 30 percent chance we'll see some showers or thunderstorms as the front goes by.

No outside work planned this weekend? Me neither. You'll find me in the hammock, with a book. Unless my wife has other plans.

(SUN PHOTO: Andre F. Chung, 2007)

Posted by Frank Roylance at 10:32 AM | | Comments (0)
Categories: Forecasts

July 14, 2011

Perfect .... but 90s return next week

There is simply no better July weather available for Baltimore than the weather we're getting today. The forecast high is just 85 degrees, a couple of degrees below the long-term average for this time of year and the coolest day since June 27. Low humidity, a nice breeze ... so why am I stuck here looking OUT at the blue skies over the State Pen?

The weekend forecast is almost that good. Baltimore can expect highs Friday through Sunday in the upper 80s, with no rain and lots of sunshine. The 90-degree weather we've come to know and love resumes next week, with highs rising daily to 95 by Wednesday.

Headed for the beaches? You'll see 80 degrees and no more than some fair-weather clouds right through the weekend, if the forecasters have it right. Be careful with the rip currents, though.

Going west to Deep Creek? The mountain folk are expecting highs in the mid- to upper-70s, with plenty of sunshine. Again, no rain in sight.

Speaking of rain, the new Drought Monitor Map is in, and it reflects a small amount of improvement from the prior week's report. Scattered showers across the Eastern Shore appear to have diminished the extent of the drought there. But not by much.

The territory rated in Severe Drought has retreated a bit away from the coast. It's centered now over Somerset County, the southern half of Wicomico and the western half of Worcester. The territory in severe drought now amounts to 7 percent of the state, down from almost 10 percent last week.

Moderate drought persists from Talbot County south, and in southern portions of Calvert and St. Mary's counties in Southern Maryland. The rest of the state from eastern Washington County east remains in the "abnormally dry" category. 

All told, 86 percent of Maryland is rated from "Abnormally Dry" to "Severe Drought," down from 87 percent last week.

Posted by Frank Roylance at 10:07 AM | | Comments (0)
Categories: Forecasts

July 12, 2011

Forecast highs tweaked downward

So maybe we won't hit 100 degrees in Baltimore today after all. The National Weather Service forecast office in Sterling has tweaked its forecast a bit in response to new model runs. They're now calling for a high at BWI-Marshall Airport of only 95 degrees, down from the 98 they were predicting last night.

(UPDATE, 11:45 a.m.: Just as I post this, the NWS bumps the BWI forecast high today to 97 degrees. New model run, I guess. Stay tuned.)

UPDATED UPDATE, 2:45 P.M.: Tweaked again. The forecast high for BWI is now 94 degrees. The Heat Advisory  has been lifted. 

There's some acknowledgement in the morning forecast discussion , however, that their model guidance has been "running too cool," so they have not gone as low as the models suggest they should. Your weather Cooling offblogger has contended for some time that Sterling routinely undershoots Baltimore's summer heat wave highs by 2 or 3 degrees. We'll see how well they do this time.

The record high for Baltimore for this date is 97 degrees, set in 1908. That may be a bit harder to crack today than it seemed at this time yesterday. But it's not impossible.

In any case, humidity levels will remain high, with dew points in the low 70s. So they're not changing their forecast on Heat Index readings for this afternoon. They're still calling for us to top out between 100 and 105 degrees. 

That's why we remain under a Heat Advisory in Central Maryland today (Tuesday).  From Baltimore, Harford, Howard and Montgomery counties south to the Potomac, and on the Eastern Shore, heat and humidity will combine to increase the risk of heat-related illnesses. Nine people were seen in Baltimore emergency rooms Monday with heat-related illnesses, according to Brian Schleter, of the city Health Department.

We're also under a Code Orange Air Pollution Alert in Central Maryland. We never did reach Code Red levels, as had been forecast for Monday.

The predicted cool-off is still en route. Forecasters had said we'd drop to the high 80s in BaltimoreBaltimore temperatures by Wednesday. But that's been bumped to 92 degrees, with a continuing low risk of showers and storms. The promised cold-front passage is now on the agenda for Wednesday morning and afternoon, moving from north to south.

Winds from the northwest behind the front will finally bring daily high temperatures down into the mid-80s Thursday through Saturday, with noticeably drier conditions. That's actually just a shade below the normal values for this time of year. Should feel great.

The heat and humidity start to return on Sunday as the high moves off the coast and we get the return flow from the south. But forecasters are promising "no big heat waves expected through Monday."

(PHOTO: Reuters, Laszlo Balogh)

Continue reading "Forecast highs tweaked downward" »

Posted by Frank Roylance at 10:29 AM | | Comments (0)
Categories: Forecasts

July 11, 2011

Heat Advisory posted for Tuesday as temps near 100

With forecasts calling for highs for Baltimore near 100 degrees Tuesday, the National Weather Service has posted a Heat Advisory from Harford County to Montgomery and south to the Potomac River. Heat Index values will reach 102 to 106 degrees.





Posted by Frank Roylance at 1:35 PM | | Comments (0)
Categories: Forecasts, Watches and warnings

Today's air unhealthy for everyone

Planning to head out for a jog today? Better skip it. Air pollution levels in the Baltimore region Monday are forecast to reach levels considered unhealthy for everyone, not just vulnerable groups such as children, ther elderly and the sick.

The Maryland Department of the Environment has issued a CODE RED Air Pollution Alert for Carroll, Baltimore, Harford, Howard, Cecil and Anne Arundel Counties, as well as Baltimore City. All Baltimore Haze Camresidents are urged to avoid strenuous activity or exercise outdoors today.

In addition, Clean Air Partners, a consortium of regional governments, private sector and advocacy groups, advises Marylanders to turn off lights and electronics when not in use to reduce electric power demand that contributes to air pollution from power plants; avoid lawn mowing; telecommute or use public transit; avoid using chemicals in your lawn or garden.

UPDATE, 1:50 p.m.: This is the first Code Red prediction from the MDE this year, although pollution levels have reached Code Red threshholds on five previous dates (June 8-10, and July 2 and 5). That's fewer Code Orange-or-worse days than last year at this time, but MDE spokesman Randy Mosier said "this yerar's been a little more intense," with more Code Red violations than last year.

Aircraft flown by the University of Maryland over the weekend detected high ozone levels aloft over Virginia. "With a south southwest flow of air, they know that stuff's coming our way," Mosier said.

Today's Code Red forecast was also spurred by a prediction that the development of a bay breeze today would bring a wall of wind up from the southeast, trapping pollutants along the I-95 corridor, in Harford County in particular. Unless a thunderstorm develops, or cloud cover thickens, "I don't think there's much indication we won't hit those [Code Red] levels," Mosier said.

Earlier post resumes:

A Code Orange Pollution Alert has been posted for Frederick, Montgomery, Prince George's, Charles, St. Mary's and Calvert counties. On the Eastern Shore, the Code Orange alert is extended to Kent. Queen Anne's, Talbot, Caroline, Dorchester, Worcester Wicomico, Somerset and the Maryland beaches.

A Code Orange Alert means the air is unhealthy for vulnerable populations, such as children, the elderly and those with cardiovascular illnesses.

The National Weather Service is predicting high temperatures around 94 degrees Monday at BWI-Marshall Airport. The high could reach 95 degrees in downtown Baltimore. And these forecasts  frequently prove to be too low on hot summer days in Baltimore. Relief coming

In response to the hot-weather forecast, the Baltimore City Health Department has issued a Code Red Heat Alert, opening cooling shelters across the city and sending outreach workers into the community to check on vulnerable residents.

The city has recorded two heat-related deaths so far this season. "Poor air quality combined with high heat and humidity can lead to respiratory distress. It is vitally important that all residents, but especially the elderly, stay cool, drink plenty of clear liquids, avoid alcohol and take it slow if you need to be outside," said Baltimore Health Commissioner Dr. Oxiris Barbot. For more information: 

Tuesday is expected to be even hotter, with highs forecast to reach 97 degrees at BWI and downtown. But the forecast discussion from Sterling this morning says the forecast models are in broad disagreement about that. So there's some chance we could see triple digit temperatures Tuesday afternoon at BWI. 

The record high temperature for Baltimore on a July 12 is 97 degrees, set in 1908. It's relatively low-hanging fruit - the coolest Baltimore record high for any date in July.

At the very least, we run the risk of triple-digit heat index readings as dew points near 70 degrees drive up the humidity side of the equation. That could get us into Heat Index numbers of 105 degrees or more.

Relief (map above) comes in the form of a cold front due to cross the region Tuesday night. That would drop the humidity level as drier air moves in from the northwest. Temperatures would drop a bit, into the mid-to-upper 80s for the balance of the week.

Posted by Frank Roylance at 10:43 AM | | Comments (4)
Categories: Forecasts

July 8, 2011

Man the pumps! Heavy rain coming

Radar shows what forecasters predicted. There are heavy showers and thunderstorms moving toward the Baltimore area this afternoon.

One forecast model (see clickable map) says they could dump as much as 4 to 7 inches of rain on some locations. But even if that's an outsized prediction, we're almost certain to see several inches at least. Here's what Eric the Red is seeing this afternoon:

"This afternoon and eve ... we appeared primed for a round of potentially torrential downpours. Storms are popping up on radar out ahead of the main event. Models vary greatly ... with the GFS coming in with a modest 0.50 inch ...The WRF, however, is totally jiggy with this storm, and has a forecast of 4 to 7 inches of rain for this afternoon and tonight... They both seem a little (or alot) under/over done, but if I had to lean, I'd go toward the higher end. A 1 to 3-inch rain event seems like a good bet, with locally higher totals."

Later, he added, "Some of these [storms] will likely be severe, with strong winds and/or hail. There's also the risk of a small tornado."

Indeed, the National Weather Service this afternoon posted Severe Thunderstorm Watches until 9 p.m. for all of Central Maryland, and a Flash Flood Watch until 6:45 p.m. for all the northern tier of counties from Washington east to Harford. One to three inches of rain are predicted with the storms.

What are you seeing? Leave us comments until the computer goes under.


Posted by Frank Roylance at 3:53 PM | | Comments (5)
Categories: Flooding, Forecasts

July 7, 2011

And the heat goes on ...

Looking for some relief from the 90-ish temperatures and high humidity? Be here tomorrow (Friday). The NWS folks in Sterling are offering us a high of only 84 degrees at BWI-Marshall Airport. And that's about the only break we see in the forecast.

There's a frontal boundary draped across the mid-Atlantic states, with hot and humid to the south and cooler, drier air to the north. That's been responsible for the monotonous string of hot, tropically humid days and scattered showers. We've had just two high temperatures at BWI since July began - 89 degrees on the 1st, 4th and 6th, and 93 on the 2nd, 3rd and 5th. There's also another Code Orange Air Pollution Alert in effect today. Breathing outdoors will be unhealthy for sensitive groups. NOT breathing is also not recommended. Go indoors and breathe there.

The system is finally going to get booted off the coast in the next two days as a coastal low moves up the Atlantic seaboard. We'll see some stepped-up showers and storms in the process, especially along the Mason-Dixon line, forecasters said. It will also bring us some slightly cooler (mid- to upper-80s) temperatures Friday and Saturday.

Forecasters say we could see up to a quarter inch tonight, Friday and again Friday night before the system finally gets by us. Any rain would be welcome. Eighty-seven percent of Maryland is now rated abnormally dry, with the southern half of the Eastern Shore and extreme Southern Maryland now officially in drought. The three southernmost Shore counties are now in severe drought, according to the federal Drought Monitor

The USDA Weather and Crops report for July 3 quoted crop reporters' concern for the corn crop "due to lack of much needed rainfall. Some areas reported signs of stress and producers in Delaware reported areas of damage to the corn crop due to excessive drought conditions. Another concern was rainfall may come too late to help crop progress."

The arrival of dry high pressure behind the front will clear the skies, but it will also send afternoon highs back into the 90s for the first half of next week before another cold front arrives with renewed chances for some rain.


Posted by Frank Roylance at 10:11 AM | | Comments (0)
Categories: Forecasts

July 5, 2011

More 90s due this week and next

We're getting close to the height of summer heat for Central Maryland, so it's no surprise that forecasters are calling for highs near 90 degrees at BWI-Marshall Airport Tuesday and Wednesday.

The heat and strong sun are helping to stoke air pollution chemistry. Central Maryland is under 4th of July Baltimoreanother Code Orange air pollution alert Tuesday. The alert means air pollution levels may become unhealthy for sensitive groups, including children, the elderly, and people with respiratory or cardiac conditions. The effects can be minimized by avoiding strenuous outdoor activity.  

The average daily high temperature for Baltimore at this time of year is 87 degrees, one tick short of the 88 degrees that marks the maximum for the year. That's reached between the 16th and the 25th of July. After that, the daily norms begins to slip as the length of the day shortens and sun angles begin to decline.

There's a front stalled across the region this week, which explains the persistent, if slight, chance of showers and thunderstorms Tuesday through Thursday. After that, high pressure in the Great Lakes should give the system a shove from the northwest. That will bring in some drier air, but only slightly cooler, with weekend highs close to the seasonal averages. We'll take it. Great beach weekend ahead. Don't forget the sunblock.

By early next week, the highs will be pushing back into the low 90s. For Hot-in-Baltimore contestants, the year's tally of 90-plus days now stands at 12 through Monday. The lowest guess was 15 days, by BD. By this time last year, we had counted 22. The annual average is about 29 days.

(SUN PHOTO: Kim Hairston 2011)

Posted by Frank Roylance at 11:22 AM | | Comments (1)
Categories: Forecasts

June 24, 2011

Last weekend in June will be beautiful

Got a wedding scheduled this weekend? A family barbeque? A roofing job? Or do your plans involve nothing more than a beer, a boat or a tiki bar? If so, you have been living right.

Forecasters out at Sterling have served up a perfect weekend, with highs in the mid-80s, a little breeze, lots of sunshine and stars. The high humidity of the past few days should be dissipating today as a (mostly) dry cold front sweeps through and high pressure builds into the region from Baltimore weatherthe north.

Some spots to our west could see some scattered showers this afternoon. But mostly, for better or worse, we're done with showers and storms until next week.

By late Sunday, the high pressure will be moving offshore, and that will put us into the return flow, from the south, around the backside of the clockwise-spinning high. That will bring in more humidity from the South, and raise the risk of showers and storms by late Sunday night. Daytime temperatures shouldn't change much, however.

That will start to change by Monday, as low pressure moving through the Great Lakes begins to draw more heat and humidity into our region ahead of the next cold front. That will mean highs moving back into the low 90s by Tuesday and Wednesday, and rising storm chances.

High pressure returns after mid-week, if the forecasters are right, bringing us back into drier air. But temperatures will still flirt with the 90s as we get closer to July, and the peak of the hot season for Baltimore.

Speaking of heat, the high at BWI Thursday was 87 degrees. That was far from the record. The low temperature dropped to 74 degrees before midnight, so we just missed tying the record high minimum for the date - 75 degrees, set in 1943. And that's okay.

(SUN PHOTO: Gene Sweeney Jr., 2009)

Posted by Frank Roylance at 11:04 AM | | Comments (1)
Categories: Forecasts

June 23, 2011

Tropical humidity continues; relief on the way

Opened the door this morning and thought I was in Florida. This high humidity, straight from the Gulf of Mexico, is forecast to continue today. But there is some relief in the cards by Sunday.

First though, we're looking at another high near 90 degrees today. And the NWS is once again AccuWeather.compredicting a 30 percent chance of showers and thunderstorms. Even higher probabilities forecast for Wednesday came to nothing for most of us. Forecasters seem to be doubting their models again today. So maybe ... or maybe not.

We can use whatever falls, although the extent of moderate drought in Maryland has not changed since last week.

Wednesday's high of 91 degrees at BWI-Marshall Airport was a long way from the 100-degree record for the date, set in 1988. But the overnight low this morning of 76 degrees appears to have beaten the previous record-high minimum of 75 degrees, last matched on June 23, 1943. If we don't drop below that before midnight tonight, we should have a new record for warm nights on June 23.

So far this season BWI has recorded nine days with highs of 90 degrees or higher. We may well top 90 again today, and there's a 90-degree high predicted for Friday, too. There may be still more in the cards next week before the month ends on Thursday.

But so far we're running well behind the pace of 2010. By this time last year we had racked up 14 days in the 90s, with seven more to come before the end of June. Doesn't look like we're going to be anywhere near that hot.

The humidity should be with us through Saturday. By Sunday, another cold front and a wind shift should bring us some dry air flow out of Canada, and seasonable highs in the mid-80s through Tuesday before the 90-degree heat and humidity return.

Posted by Frank Roylance at 10:06 AM | | Comments (4)
Categories: Forecasts

June 22, 2011

U2 fans may face a stormy evening; or not...

UPDATE, 6 p.m.: Looks like good news for U2 fans. The risk of storms this evening has dropped to 20 percent - "slight." And there is nothing on radar ATM. Enjoy. 

UPDATE, 4 p.m.: Now it's a tossup. NWS forecasters have eased back slightly - from 60 percent to 50 percent - on the chances downtown Baltimore will see showers and thunderstorms this evening. That slips to 30 percent overnight.


Earlier post below:  

Tens of thousands of U2 fans headed for the M&T Bank Stadium this evening should come prepared for the possibility of showers and thunderstorms. And some of those storms could Lightning Ravens Stadiumbecome severe, with up to a half-inch of rain, hail and damaging winds

Sound like fun? Maybe not. The concert and the storms come in the middle of Lightning Safety Awareness Week. If you can hear thunder, you are at risk of being struck by lighting. And the safest place to be is inside. Or, as the National Weather Service puts it: "When thunder roars, go indoors!"

Heat near 90 degrees and tropical humidity are expected this afternoon as the 7 p.m. concert time nears. Forecasters out at the regional forecast office in Sterling, Va. are calling for a 60 percent chance of showers and thunderstorms, mostly after 4 p.m. A quarter- to a half-inch of rain is possible.

The storm risk continues until about 8 p.m., with another quarter- to a half-inch of rain possible into the evening. But some showers and storms could linger into the overnight hours.

"Some of the storms may become severe, capable of producing large hail and damaging wind gusts," forecasters said in a Hazardous Weather Outlook posted early this morning. 

John Jensenius, a NWS lightning expert based in Gray, Maine, said concert-goers should not depend on lightning arrestors at the stadium to protect them, should a thunderstorm strike. "When you look at events that have happened in other parts of the world, there have been soccer teams that have been struck in the field. People attending the event have to consider whether or not it is a good idea to be there" in an electrical storm.

In June 1998, several concert-goers were struck by lightning on the first day of the Tibetan Freedom Concert at RFK Stadium outside Washington.  And in August 2005, a Miami Dolphins video director survived a strike on a practice field that was surrounded by lightning arrestors. 

"If there is something coming down close to the field, it could very well strike the field or the stands without hitting the arrestors," he said. "Do they help? Yes. If you're asking whether they eliminate the threat, then the answer is no."

"Obviously, if you want to be safe, you have to get inside," Jensenius said. Or, if the stadium's inner reaches are full, "if you can get to your car, that's probably even better."

(SUN PHOTO: Doug Kapustin, 1998)

Continue reading "U2 fans may face a stormy evening; or not..." »

Posted by Frank Roylance at 10:18 AM | | Comments (4)
Categories: Forecasts

June 21, 2011

"Unsettled" weather brings showers, storms

While it doesn't look like we're going to see another stretch of 90-degree days this week, as some forecasts last week had suggested, we are in line for a string of days in the upper 80s to, perhaps AccuWeather.com90 degrees, with plenty of humidity to justify keeping the AC on.

The problem is a slow-moving low-pressure system over the Northern Great Plains. The counter-clockwise circulation around that big low is drawing warm, humid air north from the Gulf of Mexico into the southeastern part of the nation. The heat and moisture are making the air very unstable, touching off showers and thunderstorms in the Mississippi and Ohio valleys.

Forecasters say Central Maryland can expect warm (upper 80s), showery weather right through Saturday as this system moves ever-so-slowly to the east. A few of the storms could be strong to severe.

The showers could persist into Saturday. But as the big low moves into eastern Canada, we'll begin to feel the backside of the circulation, with winds shifting to the northwest. With a little luck, that will drop afternoon highs into the mid-80s by Sunday, with drier air and sunnier skies.


Posted by Frank Roylance at 10:52 AM | | Comments (0)
Categories: Forecasts

June 17, 2011

More showers on tap, and 90s return next week

You didn't think we were going to have dry, sunny, 80-degree weather all summer did you? Of course not. This is Tidewater Maryland, and it's not even officially summer yet.

So, forecasters out at Sterling continue to call for showers and thunderstorms clear through the weekend. We're stuck beneath a stalled cold front, and every little disturbance that moves along the front brings the potential for more showers and thunderstorms.

They're giving it a 50 percent chance for thunder Friday afternoon, with highs near 85 degrees at BWI.  Things will calm down overnight, but there is more of the same on the schedule for the weekend.

By Tuesday, Wednesday and Thursday of next week, they're predicting we will be counting 90-degree days again.James Willinghan photo

Last night's storms brought plenty of lightning  to places south of Baltimore. James Willinghan has once again nabbed some nice bolt shots in Howard County.

Most of the rain also fell on Southern Maryland, where it is badly needed. The CoCoRaHS Network reported more than 2 inches in La Plata and Leonardtown. Nearly 2 inches fell in Severn (although that reading would seem to conflict with the pattern suggested below). Here are some other reports:

Waldorf:  1.25 inches

Laurel:  1.07 inches

Havre de Grace:  0.99 inch

Manchester:  0.61 inch

Elkton: 0.59 inch

College Park:  0.53 inch

Pasadena:  0.48 inch

Reisterstown:  0.40 inch

Easton:  0.23 inch

Jarrettsville:  0.17 inch 

Hamilton (Baltimore City):  0.13 inch

Towson:  0.05 inch

(PHOTO: James Willinghan. Used with permission.)

Posted by Frank Roylance at 10:59 AM | | Comments (0)
Categories: Forecasts

June 16, 2011

Clouds, sprinkles, showers and storms are welcome

They're calling it "unsettled" weather out in Sterling. It's a complex set of low-pressure systems in eastern Canada and the Great Lakes, and an approaching cold front, which is forecast to stall across the forecast area and return as a warm front next week.

It all adds up to plenty of clouds for Central Maryland through the weekend, with periods of sprinkles, showers and thunderstorms.


Daytime temperatures will struggle to reach 80 degrees today, but they will begin to creep higher tomorrow and Saturday, settling in the upper 80s through the weekend to near 90 degrees by the middle of next week.

Whatever rain falls will be welcome. We can use the moisture. The weekly Drought Monitor report released this morning shows "abnormally dry" conditions have continued to spread north into Central Maryland since last week, to southern Baltimore, Carroll and Harford counties. They now encompass 63 percent of the state.

Dry conditions are worst on the Lower Eastern Shore, with everything south of the Chesapeake Bay Bridge now in "moderate" drought. Extreme Southern Maryland - including the lower half of St. Mary's County and the southern tip of Calvert - is also now in moderate drought. In all, the drought conditions cover 25 percent of Maryland's territory.

The latest Weather & Crops Report from the USDA quotes a Delaware report saying: "Some storms came through with some maintenance rain to keep the corn alive and the beans coming up, but a lot more is needed." A Maryland report said: "The hot, dry weather has been tough on crops but good for hay making."


Topsoil moisture is reported "short" or "very short" in 52 percent of the state. Subsoil moisture is "short" or "very short" in 35 percent.

Rainfall for the year in Salisbury is 7.75 inches below the long-term average.

Posted by Frank Roylance at 10:34 AM | | Comments (2)
Categories: Drought, Forecasts

June 13, 2011

Perfect ...

In winter, we grouse about the weather systems the Canadians send us. They're typically too cold, or too snowy. But in summer - and the weather we had last week was decidedly summer-like, the calendar notwithstanding - our cousins to our north send us these delightfully cool and dry intervals between the oppressive bouts of heat and humidity dished up by the Bermuda Highs.

RainbowSo it's Canadian high pressure that arrived with a bang late Sunday. And we have been cooling down and drying out overnight. The year's almost-earliest sunrise on the WeatherDeck in Cockeysville (the earliest is Tuesday morning) came this morning with clear blue skies, crisp, cool air and (way too early) birdsong.

Temperatures at BWI through Thursday promise to be 15 to 20 degrees cooler than last week's, with daytime highs near 80 degrees. That's near normal for this time of year, but it will feel much cooler than that, especially in the north and northwest breezes predicted to be gusting to 20 to 25 mph.

There's a slim chance for light and scattered showers Tuesday, with an afternoon high of just 77 at the airport. But mostly we're in the clear through Thursday. At that point, the next low-pressure system will move toward the Ohio Valley, drawing warmer, more humid air up from the Gulf. We may get more showers and storms out of it by Thursday night and Friday, forecasters said.

Our temperatures will climb toward the mid 80s by the weekend. The low could stall along the way, with more showers and storms for the weekend. But for now the weekend forecast continues to show sunshine and highs in the mid-80s.

Thanks again to James Willinghan, down in Howard County, for this shot of the eerily close rainbow that appeared across the street from his house after yesterday evening's thunderstorms. Some Maryland communitiers saw trmendous rain from these storms. Here's a sampling from the CoCoRaHS Network:

Continue reading "Perfect ..." »

Posted by Frank Roylance at 10:54 AM | | Comments (0)
Categories: Forecasts

June 10, 2011

No more bets, please; Hot-in-Baltimore Contest is on

We're off to a running start, with eight days already this year reaching highs of 90 degrees or more. And 25 daring WeatherBlog readers have risked embarrassment for the chance to win a fabulous Sun trinket by correctly guessing the number of 90-plus days we'll have in 2011.

RouletteWe have 25 entries, a healthy increase from last year's total (although it's a laughable fraction of the 16,000 WeatherBlog page views we typically get in a week). Like I said, this takes daring-do.

The average number of 90-plus days in a year at BWI-Marshall Airport is 29.4, but last year we set a new record of 59.

Our players took those cues, considered La Nina, and the long-range forecasts from the Climate Preciction Center, and ran the numbers through their sophisticated climate models ... or, they added up the ages of their children, and placed their bets.

They range from a low of 15 days, to a high of 56. Median= 40; mean=36.24. No one guessed above last year's record, although we are now ahead of last year's pace. The majority - 19 guesses - came in higher than the average, anticipating another hot summer, if not one to match last year's. 

And now the wait begins. We will close the contest and award our prize (or prizes; we have three doubles) on or about Oct. 15, unless we're still seeing 90-plus highs. (Please, God, no!)

The winner will be the person closest to the actual total, without going over. Good luck!

(SUN PHOTO: Jed Kirschbaum, 2005)

Posted by Frank Roylance at 5:35 PM | | Comments (0)
Categories: Forecasts

More heat, more storms, more sweat

What? All those Severe Thunderstorm Watches late yesterday and your place got zilch? Yeah, me too. A little thunder, a few flashes of lightning, and not a drop of rain on the WeatherDeck in Cockeysville. We were watering the grass again this morning.

But rest assured there were some serious storms last evening. CoCoRaHS Network observers report Deale, in Anne Arundel County, got more than 1.5 inches of rain. Over in Queenstown, in Queen Anne's County on the Eastern Shore, they reported more than an inch. Columbia, Easton and St. Michaels all saw more than a half-inch Baltimore lightningof rain in storms.

Even Hamilton, in Northeast Baltimore managed more than a third of an inch.

BGE crews went to work and restored nearly 45,000 customers who lost power as a major storm crossed the central portion of ithe utility's  service area. BGE expects they'll all be back online by this evening. And then repair crews can tackle whatever the next round of storms brings.

Forecasters expect a 60 percent chance of more storms Saturday, slipping to 40 percent Sunday, with highs in the mid-80s.

Thursday night's storms put on quite a show in some places. William " Bear" Stifler, in Hampden, shot this great image of lightning over Baltimore. He may get more chances today. The National Weather Service says there's a 30 percent chance that "scattered" showers and storms will pop up again late this afternoon.

Thursday's 100-degree readings at BWI (it was 103 at the Inner Harbor) took their toll on the region's most vulnerable citizens. The Baltimore Health Department reported at least 14 patients were taken to emergency rooms Thursday, including six cases of heat exhaustion.

The department's spokesman, Brian Schleter also noted that  area emergency rooms saw a spike in asthma-related admissions on Wednesday. Forty-one were reported, about 14 more than normal. "Poor air quality is the likely culprit," he said. A Code Orange Air Quality Alert is posted again Friday for Central Maryland. That means breathing the air outdoors may be unhealthy for vulnerable groups.

The city also recorded 480 visits to cooling centers at the city's senior centers on Wednesday, when the high was 99 at BWI. 

In the meantime, while it may not feel quite as hot today (Friday) as it was yesterday, the high temperature at BWI-Marshall Airport is headed back into the 90s this afternoon. The official forecast high is 92 degrees, well short of the record of 97 degrees, set in 1964. But then again, the NWS almost always undershoots the mark on summer highs in Baltimore...

Dew points remain high, too, so it will continue to feel sticky and stuffy. But, as my sainted mother always assured me, "It will be better Monday."

(PHOTO: WIlliam "Bear" Stifler, Hamilton. Used with permission.)

Posted by Frank Roylance at 10:36 AM | | Comments (0)
Categories: Forecasts

June 9, 2011

NWS predicts high today of 103 downtown

Sun weather station

The National Weather Service is now predicting a high temperature Thursday afternoon of 103 in downtown Baltimore, and 101 at BWI-Marshall Airport. The downtrown Heat Index could reach 109 degrees.

UPDATE, 5:00 p.m.: The high on Thursday at the Maryland Science Center, on Baltimore's Inner Harbor, was 103 degrees. The airport high was 100 degrees, breaking the 98-degree record first reached in Baltimore on this date in 1874, and most recently matched in 1933.

The record high for Baltimore in June is 105 degrees, reached downtown on June 29, 1934.

If forecasters are right, this would be the first 100-plus reading at BWI since last July 25, when it was 100 degrees.Sun weather station

One other hot fact: Thursday's Baltimore temperatures topped 95 degrees for the fifth time this year. That ties with 1895, but remains one less than the record six days with 95-plus weather before June 9, in 1925.


BTW, here are a few forecast highs today from across the nation's "Hot Belt":

Miami, FL:  86 degrees

Atlanta, GA:  95 degrees

Dallas, TX:  94 degrees

Las Vegas, NV:  93 degrees

Los Angeles, CA: 71 degrees 

Posted by Frank Roylance at 12:39 PM | | Comments (1)
Categories: Forecasts

100s possible today; not much better Friday

The only hopeful note in today's forecast for Central Maryland is the possibility of some showers and thunderstorms. The rest is dismal: temperatures near 100 degrees (I'm betting BWI tops that, as Frederick did Wednesday), and the prospect of more hot (mid-90s) and humid weather Friday.

If you're just done with this stuff, then curl up beside the air conditioner and do nothing until AccuWeather.comMonday, when forecasters promise we'll see the start of several delightfully dry, sunny days with highs in the low 80s.

But if you venture outdoors, there is plenty of misery on tap between now and then.

Thursday seems likely to be the hottest day of this bout of July-in-June weather. The forecast high for BWI-Marshall Airport today is 99 degrees, which would beat the record for the date, which has stood since 1933, by a degree. And the forecasters note that "a few locations will reach the low 100s this afternoon." Count on it. And look for Heat Index readings around 105 degrees or more.

It's no better at the beach if you're not in the water. Ocean City reported 97 degrees at 1 p.m. 

All the by-now-familiar warnings are up: A Heat Advisory for all of Maryland weast of the mountains and on the Upper Eastern Shore; a Code Red Heat Alert in Baltimore, and a Code Orange Air Quality Alert for all of Maryland east of the Appalachians. 

Hot BaltimoreWe are victims of a summer-like Bermuda High parked over the Atlantic. The clockwise spin around the high is dragging hot, humid air off the Atlantic and the Gulf of Mexico and sending it our way.

Add a southwesterly component to the winds, and you get air moving over the Appalachians, and down the eastern slope. That compresses the air and heats it even more.

What relief we get today will come in the form of upper-level disturbances that will be riding along with the breeze, triggering some showers and thunderstorms.

Forecasters say the storms, and perhaps an isolated severe storm with hail and damaging winds, will be felt first in the mountains to our west. They could last long enough to affect the I-95 corridor by early evening, but as the air cools, the activity will diminish toward midnight.

UPDATE: 1:15 p.m.: The NWS has issued a Severe Thunderstorm Watch for Maryland from Carroll and Frederick counties west to Garrett. 

Unfortunately, the storms aren't the cure we need. Hot and humid weather will persist into Friday, with a forecast high of 94 for BWI, our fourth-straight day in the 90s. Scattered showers and thunderstorms may wet us down a bit, especially toward late afternoon and evening. 

The arrival of a "back-door cold front" - a kind of warm-front moving in reverse that approaches from the northeast rather than the northwest - will stall here, keeping us in unsettled weather, with showers and thunderstorms on Saturday. But daytime highs will hold in the mid-80s.

Better yet, a real cold front is due by Sunday, clearing the air, lowering the humidity at last, and dropping daytime highs to the low 80s into next week. And it will be OK to go outside again.

(SUN PHOTO: Kenneth K. Lam, June 2011)

Posted by Frank Roylance at 10:18 AM | | Comments (1)
Categories: Forecasts

June 8, 2011

Three more days in 90s for Central Maryland

On Tuesday, the instruments at BWI-Marshall Airport didn't reach 90 degrees until 2:54 p.m. And that was the day's high. Today, Wednesday, the airport is already reporting 89 degrees shortly before 11 a.m. 

The forecast from here isn't much better. The National Weather Service forecast office in Sterling, AccuWeather.comVa. is calling for a high of 97 degrees at BWI today, and 96 degrees on Thursday. The prediction is for 98 degrees in downtown Baltimore today, and 97 Thursday.

There is a Heat Advisory posted for Central and Southern Maryland from noon to 8 p.m. today, warning of temperatures and humidity that will combine to produce Heat Index numbers as high as 105 degrees. We can probably count on the same tomorrow.

Also again today: A Code Orange Air Quality Alert, covering the entire state east of the mountains. It means that breathing the air outdoors today will be unhealthy for sensitive groups. And, Baltimore's Code Red Heat Alert remains in force through Thursday, with cooling shelters open again across the city.Heat Baltimore

The first relief is likely to be a weak cold front due here late on Thursday, forecasters say. The NWS is calling for a 40 percent chance for showers and thunderstorms, mostly before midnight Thursday.

But as refreshing as that sounds, hot air at the surface isn't likely to be changed much by this front, which the NWS called a "so-called cold front" in this morning's forecast discussion. That will mean MORE 90-degree weather on tap for Friday, reaching 92 degrees at the airport, if the forecasters are right.

Keep in mind that the long-term averages for Baltimore at this time of year are in the low 80s. This is weather we expect to endure in mid-July.

More significant relief, bringing high temperatures back to the averages, will have to wait until Saturday. A lingering frontal boundary will keep clouds in the sky on Saturday, with a continuing 30 percent chance for storms. Each will help bring daytime highs back to the low 80s. But it will remain quite humid.

Finally, on Sunday, a stronger cold front will sweep all this stuff away, leaving us with sunshine and drier air to start the new week.

For the Record Watch, here are the marks we're aiming for in the next two days:

Wednesday: Baltimore's record high for June 8 is 97 degrees, set at BWI in 1999. Record-high minum is 76 degrees, last reached downtown in 1925

Thursday:  Baltimore's record high for June 9 is 98 degrees, last reached downtown in 1933. Record-high minimum is 78 degrees, also set in 1933.

(SUN PHOTO: Jed Kirschbaum, 2011)

Posted by Frank Roylance at 10:56 AM | | Comments (0)
Categories: Forecasts

June 7, 2011

Record highs possible Weds., Thurs.

If you liked those record highs in the upper 90s last week, you're going to love the middle of this week. Forecasters say with summer-like high pressure settling over the region, Central Maryland can expect high temperatures Wednesday and Thursday in the upper 90s, at least. And on Thursday, they said, "It's entirely possible 100 can be attained within the [forecast area]."

Heat humidity BaltimoreAnd, we will have dew points in the 70s again, too, just like last week. That means mid-summer Chesapeake humidities. So look for Heat Index readings well into the low 100s, Code Red Alerts and Air Quality Alerts, as well.

In fact, the Maryland Department of the Environment has already posted a Code Orange Air Quality Alert, from Frederick County to Cecil, and south to the Potomac River. The alert means that air pollution levels will be sufficient to be unhealthy for people in sensitive groups, including children, the elderly and those with respiratory illnesses.

Today may be the best we can do until a cold front arrives Friday morning to cool things down and water the dirt. The forecast calls for partly sunny skies and a high of 89 degrees at BWI-Marshall Airport, although we can probably count on going a few degrees beyond that. There is some chance of an isolated thunderstorm. NWS

The real misery begins Wednesday, with a forecast high of 95 degrees, which would threaten the record of 97 degrees, set on that date in 1999. Skies should be mostly clear, with no relief from the sun, heat and humidity.

Thursday looks even worse, with a forecast high of 98 degrees at the airport (and 99 downtown) Count on something a few degrees higher. The record for a June 9 in Baltimore is 98 degrees, set back in 1933, so I'm watching for a new record.

Friday's high is forecast to reach 90 degrees, but the passing cold front will bring more chances for some thunderstorms, and usher in cooler, more seasonable highs in the 80s for the weekend.

The count of 90+ days at BWI so far this year stands this morning at four. At this time last year we had seven. But we may add three or four more this week.

The Sun's Hot-in-Baltimore contest will accept entries through Friday. Guess the total number of 90+ days this year at BWI and win a cheap Sun trinket. So far, we have 21 contestants, with guesses ranging from 15 to 56. The long-term average for BWI is 29.4 days; the record (in 2010) is 59. Leave a comment or send me an email message with your guess.

(PHOTO: Sam Friedman, Patuxent Publishing, 2011)

Posted by Frank Roylance at 10:03 AM | | Comments (0)
Categories: Forecasts

June 3, 2011

Sunday storms only bump in fine forecast

If you've got a wedding planned, or a roofing job, or a retirement party, the next seven days will be just what your planners ordered.

NWSThe forecast from the NWS forecast office in Sterling, Va., sports a 30 percent chance of thunderstorms Saturday night or Sunday afternoon. But the rest of the grid looks perfect, with sunny to mostly sunny skies, and highs mostly in the low- to mid-80s - just a few degrees above the long-term norms for the region.

And look at this dew-point forecast map. DPs in the 40s! Sweet! Outdoor dining at its best.

The overnight low Friday morning was 50 degrees at BWI, and we'll likely be back into the 50s tonight. Some locations in the mountains to our west could see lows in the 40s, forecasters said.

Our first chance for a thunderstorm would come late Saturday, most likely after 8 p.m. as a cold front slowly approaches the region. Chances may be a bit better for storms Sunday afternoon.

"Severe threat is not certain," forecasters said. "But if one exists, hail would be the primary concern."

Some rain would be welcome, especially down on the Lower Eastern Shore. Three counties there are experiencing moderate drought, the northeastern-most extension of the far more serious dry conditions that have been ravaging agriculture in Texas, New Mexico and parts of the Deep South.

Behind the cold front, on Monday, skies should be mostly sunny again through mid-week, with highs in the 80s. The next chance for rain would come with the next cold front passage, on Thursday, forecasters said.

And this note to Weather Blog readers: If you've tried to post comments, you've noticed the feature has been shut down. That's temporary, in response to what's being described as a "particularly aggressive" spam attack: tens of thousands of comment spam messages last night that knocked down the platform used by all The Sun's blogs. 

The IT folks are working on it, and will restore the comment feature as soon as possible. Thanks for your understanding. If you need to contact me in the meantime, email is still working.

Posted by Frank Roylance at 11:14 AM | | Comments (0)
Categories: Forecasts

June 2, 2011

Prayers answered; cooler and dry ahead

Those "scattered" thunderstorms seem to have scattered away from Baltimore as the promised cold front pushed through yesterday. We could see tremendous thunderheads to the south and east of the city early Wednesday evening (photo), but the rain all stayed away.Thunderhead Baltimore

Here are some rain totals from the CoCoRaHS Network, just to prove that some locations did, in fact, see rain.

St. Michaels, Talbot Co.:  0.46 inch

Bowie, PG Co.:  0.30 inch

Camp Springs, PG Co.:  0.26 inch

Forestville, PG Co.:  0.22 inch

Dunkirk, Calvert Co.:  0.18 inch

No matter. We all are feeling the relief today (Thursday) as cooler, and much drier air presses in from the northwest behind yesterday's cold front. Temperatures could reach 87 degrees this afternoon at BWI-Marshall Airport. But that's 11 degrees cooler than yesterday, and dew points have dropped from the 70s yesterday to the 40s today, ending the suffocating humidity we've had to cope with since the weekend.

So open those windows tonight and enjoy the breeze. You might even need a blanket as overnight lows fall into the 50s.

NWSThe fresh air is coming with gusty winds. Forecasters out at Sterling say we could see northwest gusts to 25 or 30 mph. The combination of winds and low humidity has raised the danger of wildfires during the afternoon and early evening. So crush those smokes.

Looking ahead, forecasters see even cooler temperatures Friday and Saturday, with highs in the low 80s. There is a low risk of thunderstorms Saturday and Saturday night as more moisture arrives from the Gulf. But mostly skies will remain sunny into next week.

Temperatures will also begin to climb into the mid- to upper-80s again as the new week begins. And humidity levels will climb with the arrival of moisture from the Gulf.

(SUN PHOTO: Frank Roylance, June 1, 2011)

Posted by Frank Roylance at 10:02 AM | | Comments (0)
Categories: Forecasts

June 1, 2011

Severe t-storms possible as heat breaks

A cold front drifting south and east out of the Ohio Valley today is expected to bring Central Maryland some badly needed relief from the heat summer-like heat of the past three days. But it will come with a 50 percent risk of severe thunderstorms.James Willinghan photo

The front is due here during the late afternoon or early evening. The showers and thunderstorms may start to show up after 2 p.m., forecasters said. Some may produce damaging winds and large hail. The risk continues until about 8 p.m.

Once the front goes through, we should begin to see a sharp drop in temperatures AND in the stifling humidity that has added to our misery since the weekend. Dew points will fall from the 70s, to the 40s or 50s.

Until then, however, we will have to endure another day with highs in the mid-90s. It's already 93 at The Sun's weather station at Calvert and Centre streets downtown. With a relative humidity at NWS62 percent, and the dew point at 79 degrees, the Heat Index value works out to 112 degrees. Good grief!

Obviously, the National Weather Service has posted a Heat Advisory again today from noon to 8 p.m., warning of high temperatures in the lower to middle 90s, and Heat Index values around 105 degrees (beat that already).

There is, once again, a Code Red Heat Alert in Baltimore City. Cooling centers are open. Please check on your neighbors and family members, especially the very young and the elderly, who may be without air conditioning in this weather.

And, if you are breathing, be advised the Maryland Department of the Environment has once again posted a Code Orange Air Quality Alert, warning of pollution levels that may be unhealthy for those in sensitive groups. You know who you are. Just stay indoors and avoid outdoor activity.

Up ahead, afternoon highs in the low- to mid-80s, northwest winds, clear skies and low humidity. The next chance of thunderstorms comes with the next cold front, on Saturday.

(PHOTO: James Willinghan, Howard County, May 27, 2011. Used with permission.)

Posted by Frank Roylance at 11:30 AM | | Comments (2)
Categories: Forecasts

May 26, 2011

AC working? Hot and humid ahead

If you liked last summer in Baltimore, you're going to love the next week or so. A summerlike Bermuda High spinning off the Atlantic coast will be pumping warm, humid air up from the tropics through next Wednesday, putting the Land of Pleasant Living into the steam bath.

AccuWeather.comThe National Weather Service is predicting a high of 93 degrees at BWI-Marshall Airport on Memorial Day, with enough humidity to drive the Heat Index to between 95 and 100 degrees for several days early next week. And given Sterling's record of under-shooting our summer highs, I'd bet on temperatures reaching 95 or better.

 The record high for Baltimore on a May 30 (and any day in May) is 98 degrees, last reached in 1991.

Eric the Red, a professional forecaster from Baltimore and a frequent contributor here, seems to be thinking the same thing:

"Ooof. Just looked at some of the Wx charts for the latter half of the weekend, and things are trending hotter.  I'm thinking low- to now mid-90s for Monday and Tuesday. On Monday, the temp aloft (850mb/5,000 ft) is expected to be near ... 68°F, which translates to 94-95°F at the ground level.

National Weather Service"On Tuesday, the temp aloft is expected to be near ... 70°F, which is 96° or so at ground level. Ouch."

Out at Sterling, the morning forecast discussion includes this: "The synoptic [general] pattern next week is reminiscent of the predominant weather pattern from last summer that was associated with relentless heat ... Highs will generally be in the upper 80s to low 90s each day. Combined with dewpoints in the mid to upper 60s, heat indices between 95 -100F deg will be possible during the peak heating hours of the afternmoon."

For the moment, we are still waiting for low pressure over the Great Lakes - the system that has helped fuel the week's tornadoes - to weaken and move off to the northeast. It's that low, and the cold front draped from there down the Appalachians, that is keeping us in mixed sunshine clouds, and at low risk (30 percent) of afternoon and evening showers.

They're calling for a high of 89 Thursday afternoon. I'll bet on hitting 90 or more for the first time this year for Baltimore, with cooler readings closer to the water, where the bay or ocean breezes prevail. The highest risk of severe weather may come tonight, mostly inland, to the west of I-95.

Cloud cover will keep things slightly cooler (87) Friday than today, forecasters say. And by Saturday night we should be done with the rain. The Bermuda High will push west and become dominant in our forecast, and we'll be set for some real Chesapeake summer weather.

Press "Cool."

Posted by Frank Roylance at 10:31 AM | | Comments (4)
Categories: Forecasts

May 25, 2011

Sunshine and showers, then a really hot holiday

The weather service has backed off its earlier forecast for shower chances this afternoon. But the risk returns Thursday through Saturday as a south wind continues to bring loads of warm air and humidity into the region ahead of a cold front approaching slowly from the Ohio Valley, and strong sunshine AccuWeather.comstokes the atmosphere.

For the most part, though, we will avoid the really dangerous weather still threatening the nation's midsection.

"The greatest potential for severe [stoms Thursday] looks to be east of the Blue Ridge currently, where maximum heating has the best chance to be realized," forecasters said in this morning's discussion. "Large hail and damaging wind gusts will be the primary threats. Front will stall across the [forecast area] by late Friday, but begin pushing northward during the weekend."

That push will begin to clear us out as high pressure builds in on Saturday. But southerly winds circling a high-pressure system out in the Atlantic will keep the heat on. Forecast highs for BWI-Marshall Airport reach 89 degrees on Sunday, 90 on Memorial Day and 92 on Tuesday as we all head back to work. Summertime in May.

The long-term average for high temperatures at BWI in late May are in the upper 70s, so we're looking at heat 10 to 15 degrees above the norm as we turn toward the beginning of June.

Things look considerably better for those headed for the "ayshun" this weekend. Cooled by the Atlantic, Ocean City is expecting highs only in the upper 70s, with lots of sunshine from Friday on. The ocean water temperature, however, is still a bit puckersome, at 62 degrees. 

Posted by Frank Roylance at 12:08 PM | | Comments (0)
Categories: Forecasts

May 24, 2011

Mercury crowds 90 by Friday; more showers due

There seems to be little letup in sight for this showery weather. The National Weather Service has posted chances for showers and thunderstorms in Central Maryland right through Saturday as we remain stuck alongside a stalled cold front just to our north. The most likely period for storms will Thunderhead May 23, 2011be today (Tuesday) and tonight, with probabilities of 50 to 70 percent.

But that hardly seems notable given all the wet weather we've seen this month. What's new in the forecast is the first prediction of 90-degree weather for the year. That would come Friday, if the folks out in Sterling, Va. have it right. Think heat AND humidity.

UPDATE, 4 p.m.: The updated forecast now calls for a high of 89 on Friday at BWI. Given the NWS habit of low-balling hot weather at BWI, I think we're quite likely to make 90. And a sunny forecast for Sunday through Tuesday has boosted the predicted highs to 89, 90 and 92 degrees. So how's your AC working?

We're behind last year's pace for 90-plus days in Baltimore. By this time in 2010 we had already seen two (April 6, 7) and would experience three more before the month ended. We tallied 59 before the year was out, a new record.

The week won't be entirely gray. Mostly or partly sunny skies are expected (between the showers) each day through Saturday. And there is no mention of rain for Sunday or Monday - Memorial Day. So at least part of the long holiday weekend will be drip-free.

We are still dealing with a Coast Flood Advisory for the Western Shore until 6 a.m. Wednesday. High tides will run 1 to 2 feet above the norms.

The thunderstorm photo above was sent to me this morning by Karen Pierce-Blandamer, in Pasadena. It was shot Monday, looking east across the Chesapeake Bay. "Our 6-year-old daughter came in from outside yesterday evening saying, 'Doesn't this look like a mushroom cloud?'" she wrote.

It does, but thankfully it's a pretty classic thunderstorm "anvil" cloud that has caught the evening sunilight. Thanks for sharing it.

Posted by Frank Roylance at 10:27 AM | | Comments (1)
Categories: Forecasts

May 23, 2011

Warmer, more humid and showery week ahead

Seems like everyone on the block raced to get their grass cut over the weekend, taking advantage of what now looks like a brief break in our rainy weather.

The National Weather Service's 7-day forecast keeps thunderstorm chances on the boards for every day through next Sunday. We will see sunshine during the week. But the solar heating will only serve to make the rising humidity more apparent, and to stoke chances for afternoon and evening showers and thunderstorms.

A Severe Thunderstorm Watch has been posted until 6 p.m. for the entire state between the Chesapeake Bay and Allegany County, and south to St. Mary's County.   

AccuWeather.comThe main actors this week will include high pressure offshore. Clockwise circulation around the high will be pumping warm, humid air our way from the Atlantic and the Gulf. (Feel like summer by the Cheseapeake yet?) Add a series of disturbances working their way east from the Midwest and you get a showery forecast for the entire week.

The first round comes Monday afternoon as the remains of the storm system that pummeled Joplin Mo. overnight make their way east, up the Ohio Valley and across the Appalachians. That should bring us showers and thunderstorms in the afternoon and evening hours. Some of those storms are already showing up on radar as they move through Ohio.

Stronger storms are in the forecast for Tuesday as a cold front drapes across the region and stalls near the Mason-Dixon Line. Strong wind gusts and large hail are possible with those storms as they develop near the front.Tides Online

And that's about how things will remain through much of the week. Sunshine and clouds, showers and storms each day and some overnight ... Daytime highs will remain in the 80s, with Tuesday (87 degrees) and Thursday (86 degrees) now expected to be the warmest of the bunch. Average daytime highs at this time of year in Baltimore are about 77 degrees, so we will be running 5 to 10 degrees above the norms.

Take an umbrella. 

And maybe waterproof shoes. The NWS has posted a Coastal Flood Advisory until 6 a.m. Tuesdayfor the Western Shore again as southerly winds again keep the water bottled up in the bay and pressed against the western shore. Minor flooding is possible in the usual low-lying spots.

Annapolis Mayor Joshua J. Cohen says sandbags will once again be available downtown and in Eastport as the bay rises over portions of Dock, Compromise and Newman streets at high tide. The sandbags can be picked up at the 2nd Street pumping station, Mills Liquors and the Market House at City Dock.

High tide times for Maryland's Western Shore are below.

Continue reading "Warmer, more humid and showery week ahead" »

Posted by Frank Roylance at 10:36 AM | | Comments (0)
Categories: Forecasts

May 20, 2011

Foot's Forecast for the Preakness

Mr. Foot and his students have hummed up a pretty nice forecast for Preakness Saturday. Here it is:


Posted by Frank Roylance at 5:31 PM | | Comments (0)
Categories: Forecasts

Water torture ending; sun will come out, tomorrow

In the past seven days Baltimore has had six days of rain, a slow water torture that added up to 1.5 inches at BWI-Marshall Airport. And there was plenty more if you happened to be under one of the drenching thunderstorms that swept the region. The misery even came with a few tornadoes, but let's not go there.

Finally, if forecasters down at the National Weather Service offices in Sterling can be believed, it's AccuWeather.comabout to end. Saturday's forecast calls for "mostly sunny" skies and high temperatures around 80 degrees. The infield at Pimlico may still turn into a muddy slop-fest, but at least it won't be raining.

We have a few more showers to endure today first. Scattered showers are in prospect Friday, with perhaps a thunderstorm in the afternoon and early evening. The flood crest moving down the Potomac, past Little Falls and Point of Rocks today will mean high water and Flood Warnings for Washington, D.C. and Alexandria for a few more days.

But then the lazy low that has been responsible for dragging all this Atlantic moisture into the region all week, is expected to drift off to our northeast. Tonight, as high pressure begins to build into the region behind the departing low, skies will actually begin to clear, the forecasters insist.

By Sunday, winds will have swung around to the south, bringing in more humid air from the Gulf. Daytime temperatures will warm into the mid-80s, with some added risk of showers and thunderstorms in the afternoon and evening.

But the forecast for the early- to mid-week period calls for sunny skies and highs in the mid-80s. Maybe I'll finally get the grass cut.

Posted by Frank Roylance at 10:53 AM | | Comments (0)
Categories: Forecasts

May 19, 2011

And now, waterspouts?








Posted by Frank Roylance at 4:35 PM | | Comments (0)
Categories: Forecasts

May 18, 2011

So where's all the rain?

So I've been sitting here on Calvert Street for days, cranking out posts to relay dire warnings from the weather service about showers and thunderstorms and flash flooding. There have been watches and warnings and ... So where's all the rain?

BWI-Marshall Airport is reporting just 0.38 inch since early Tuesday morning. We've had only 0.13 inch here at The Sun's weather station. It seems like there's been more water lapping over the City Dock in Annapolis than has been falling across the region.

It appears that most of the rain with this stubborn "cutoff low" has been falling to our west, in the mountain counties of Maryland and down in the Shenandoah Valley of Virginia. Accident, in Garrett County reported 1.88 inches by 8 a.m. Wednesday, according to the CoCoRaHS Network.

The Potomac River is expected to crest at Paw Paw at 25.8 feet at 2 p.m. today, forecasters said - just above flood stage. Hancock was headed for 23.5 feet tonight - just below flood stage. Harper's Ferry and Sheperdstown should see peaks tomorrow, with Point of Rocks and Little Falls cresting on Friday.

The National Weather Service is reporting more than 2 inches in parts of Western Maryland, and upwards of 3 and 4 inches of rain down in parts of Virginia and West Virginia. Here's a sampling from both

Winchester, Va.:  3.4 inches

Jones Springs, W.V.:  3.25 inches

Hollymead, Va.:  2.59 inches

Bridgewater, Va.:  2.32 inches

Eldersburg, Carroll Co. Md.: 0.90 inch

Columbia, Howard Co.:  0.75 inch

La Plata, Charles Co.:  0.69 inch

Severn, Arundel:  0.66 inch

Westminster, Carroll Co.:  0.49 inch

Bel Air, Harford Co.:  0.09 inch

That's not to say we've dodged the rain here in Baltimore. NWS forecasters continue to warn there's more coming. Showers and thunderstorms this afternoon and evening could produce heavy rain and flash flooding. Some could be severe, with damaging winds, large hail and even an isolated tornado.

Central Maryland remains under a Coastal Flood Warning as persistent southeasterly winds keep water bottled up in the Chesapeake. The winds, coupled with a full moon, are making for high Tides Onlinetides in excess of two feet above normal today.  

Showers and thunderstorms remain in the forecast through Friday as the sluggish low drifts north from the southern Appalachians into the Ohio Valley.

"The heaviest rainfall is expected late this morning through this afternoon when instability will be at its highest," forecasters said.

The low is forecast to continue pumping loads of Atlantic moisture into the region, keeping us gray and drippy. Whenever solar energy is able to trigger thunderstorms, they are likely to drop heavy rain, with a risk of large hail and and damaging winds.

"This has been one of the most persistent upper lows I've ever experienced here," one forecaster said in this morning's forecast discussion. "But the end will be occurring soon."

By Friday the low will have moved into New Jersey. We'll still feel its effects, but they will be easing. And by Saturday we should see partly sunny skies with highs near 80 degrees.

Are we having fun yet?

Posted by Frank Roylance at 10:51 AM | | Comments (1)
Categories: By the numbers, Forecasts

May 17, 2011

Preakness forecast looks sunny

As soggy as we're likely to be for the rest of the week, the stubborn low-pressure system that has sent us all this rain and kept the bay lapping at our feet will be moving off by the weekend.NWS

The National Weather Service is predicting partly sunny skies and a high near 80 degrees for Preakness Day on Saturday. So while the infield may still be wet and muddy from a week of rain, at least there should be no new water falling from the sky.

Sunday looks a bit warmer and sunnier, but then the risk of showers and thunderstorms returns for the new work week. Sorry.


Posted by Frank Roylance at 3:40 PM | | Comments (0)
Categories: Forecasts

Wet and wetter; rain, storms and coastal flooding due

There may be no getting away from water today, whether it is falling on your head or lapping at your shoes. Central Maryland is under a list of watches, warnings and advisories. Here are two of the most important:


Storms May 16, 2011  EASTERN WEST VIRGINIA.







And here's a timely reminder: Don't attempt to drive through standing water. That puddle may be deeper and swifter than you think. And it doesn't take much to float your car, yourself and your kids down the river. Don't risk your life or those of the rescuers who may have to try to pluck you from your car, or a tree. Here's more: Turn Around, Don't Drown.

(SUN PHOTO: Frank Roylance, May 16, 2011)

Posted by Frank Roylance at 8:32 AM | | Comments (0)
Categories: Forecasts

May 16, 2011

Enough yet? More showers and storms due

One of these days, between work and the rain showers, I'll get to cut the grass. But for now, it's just going to keep growing as we continue to entertain showers and storms that just won't leave.

Low-pressure parked pretty much on top of us continues to spin in a counter-clockwise direction. AccuWeather.comAnd that is spooling in loads of moisture from the Atlantic Ocean. Add some daytime solar energy, and we will be kicking off more showers and thunderstorms for the immediate future.

Forecasters out at Sterling are giving us a 30 percent chance for rain this afternoon, rising to 70 percent overnight. The risk then climbs to 100 percent on Tuesday and Tuesday night before gradually diminishing to 60 percent Wednesday, 40 percent Thursday and 30 percent Friday.

During that period, we could see anywhere from 1.5 to 2.5 inches of rain, they say. And if you happen to find yourself beneath a thunderstorm, the totals could exceed that.

If they're right, Tuesday would seem to present our greatest risk of heavy rainfall and flash flooding. Keep an eye peeled for Flash Flood Watches and warnings.

Sterling has cancelled the Coastal Flood Advisory that has stood for several days on the Western Shore of the Chesapeake. But they expect to reinstate it early Tuesday. Coastal Flood Avisories continue in effect along portions of the Eastern Shore of the bay, and in southern portions of the Western Shore as onshore winds and high tides combine to raise high tides 1 to 1.5 feet above normal. Minor flooding in low-lying areas remains a risk.

We were down near Tilghman Island over the weekend and the high tides were just lapping at the tops of the bulkheads, and the bottoms of the piers. Folks there told us some of their piers had been underwater at high tides earlier in the week.

Posted by Frank Roylance at 11:23 AM | | Comments (1)
Categories: Forecasts

May 13, 2011

Get used to it: showers and T-storms through Thurs.

If you were planning any gardening, camping, hiking, parties or weddings during the next seven days, the forecast from the National Weather Service will not be a pleasant read for you today.NWS

There is no sunshine to be seen in the document, just words like "scattered showers, cloudy, possibly a thunderstorm, new rainfall amounts," and, finally, for four days running next week, "a chance of showers and thunderstorms."

At least the new grass will get a good start, right? And the pollen counts should be lower. I know I can be thankful for that.

AccuWeather.comOh, and the Coastal Flood Advisory posted a few days back has been extended to 8 p.m. Saturday, as south and east winds continue to hold water in the Chesapeake. High tides will run 1 to 2 feet above normal Friday and Saturday, with "minor" flooding in low-lying areas. The Hazardous Weather Outlook posted Friday morning also notes that the onshore winds will strengthen this weekend, and could increase the flooding to "moderate."

The problem appears to be a low-pressure area in the Ohio Valley that is drawing moisture up from the Gulf and the Atlantic Ocean. It is expected to stall for the next few days, so the counter-clockwise circulation around the low will continue to bring us unsettled weather into the middle of next week. Nice.

The highest risk for rain, storms and flash flooding today will be in the western counties. Flash Flood Watches are already up for Allegany County, including the cities of Frostburg and Cumberland. One to two inches of rain are expected there today. Amounts could be higher in thunderstorms.

The big rain risks for Central Maryland come Saturday night and Sunday, when the chances rise to 70 and 80 percent. Forecasters aren't entirely sure how bad it may get here. But they do seem to be hinting that Sunday could be more problematic than Saturday.

Not that it matters much. Wet is wet.

Posted by Frank Roylance at 10:13 AM | | Comments (0)
Categories: Forecasts

May 12, 2011

Beautiful weather goes downhill from here

It's been sweet, all this sunshine, comfortable temperatures and cool nights. But it's coming to an end over the next few days as the high pressure moves off and a couple of storm systems move our way from the Plains states. Next week looks as rainy as this one was sunny.

We'll be in the mid-70s again this afternoon, with plenty of sunshine. Friday should see some sunshine, but there will be more moisture moving up from the south, adding to our cloud cover for AccuWeather.comthe first time in quite a while. That will keep afternoon highs in the low 70s.

But forecasters out at the National Weather Service forecast office in Sterling say a low developing over the Central Plains will be moving slowly eastward by then, dragging a cold front our way. Our first shower chances comes late Friday.

Here's's take on the rain headed this way.

Moisture continues to rise on Saturday. And depending on how unstable the air becomes, there is a 70 percent chance of showers and thunderstorms Saturday, rising to 80 percent Saturday night. Periods of showers and storms continue into Sunday, and there's some chance we could see heavy rain and a risk of flash flooding.Tides Online

Forecasters seem a bit skeptical of what the models are telling them. But they've gone ahead and posted a Hazardous Weather Outlook that includes notice that showers and thunderstorms Sunday could produce "very heavy rain." A few of those storms could also generate damaging wind gusts.

In the meantime, persistent breezes out of the south are piling water into the Chesapeake and up against the western and eastern shores. the NWS has issued a Coastal Flood Advisory until 6 p.m. Thursday noting the possibility of high tides 1 to 2 feet above normal. That could mean "minor" coastal flooding at the time of high tides.

Here are some of the upcoming tide times:

HAVRE DE GRACE...5:48 PM AND 6:39 AM...
BOWLEY BAR...3:26 PM AND 4:17 AM...
POINT LOOKOUT...9:07 AM AND 9:58 PM...

INDIAN HEAD...3:50 PM AND 4:26 AM...
AQUIA CREEK...2:36 PM AND 3:12 AM...
GOOSE BAY...11:56 AM AND 12:32 AM...
COLTONS POINT...10:46 AM AND 11:22 PM...


Continue reading "Beautiful weather goes downhill from here" »

Posted by Frank Roylance at 12:03 PM | | Comments (0)
Categories: Forecasts

May 9, 2011

Beautiful week ahead - sunny, 70s

All those rainy days, all those chilly, damp days ... Put them all behind you this week. Forecasters are serving up at least four more days of perfect spring weather for Central Maryland.

After a fine weekend, we're looking at partly to mostly sunny weather right through Thursday, with highs in the 70s and lows in the 40s and 50s. We can thank a big high-pressure system that is expanding out of Canada's Hudson Bay into the mid-Atlantic region with relatively cool, dry air.

Coupled with a low out over the Atlantic, the Canadian high is drawing the cool air southward. It is also acting as a block to prevent the advance of storm systems from the Plains states to our west. It's also keeping away the record heat they're expecting in the Southern Plains. 

By week's end, however, the high will have moved far enough east to admit the low-pressure trough from the west. We'll also begin to feel the return flow from the clockwise movement of air around the high, bringing more humidity in from the south.

Cloud cover by Friday will prevent temperatures from rising very much, forecasters say. So we're looking for rising chances for showers and thunderstorms Friday night, persisting through the weekend. High temperatures will hold near 70 degrees.

So, nice workweek, with rain risks for the weekend.  

Posted by Frank Roylance at 11:05 AM | | Comments (0)
Categories: Forecasts

May 5, 2011

Summer outlook leaning to cool, wet

It's not entirely clear how the approaching summer season will turn out for Central Maryland. The region seems to be just outside of the regions where the forecasters' greatest confidence lies. We're in the "EC" zone, which means "equal chances" for warmer or cooler, wetter or drier than average.

But if it means anything at all, we seem to be closer to regions where the predictions lean toward relatively mild and rainy weather from June through August.

Here are the long-range forecast maps for the nation, from the NOAA Climate Prediction Center.

Posted by Frank Roylance at 9:06 AM | | Comments (2)
Categories: Forecasts

May 4, 2011

Showers and cold air slow to depart

Overnight rain dropped more than a half-inch on The Sun's weather station at Calvert and Centre streets, with the highest rain rates around 6 a.m.  The rest has been dribs and drabs, but it adds up.  

Sun Weather Station

Other spots have seen more, especially south of Baltimore. Anne Arundel County had some serious storms, with at least five schools closed this morning due to power outages. Here's more from the CoCoRaHS Network:

South Gate, Anne Arundel:  1.18 inches

White Marsh, Baltimore Co.:  0.78 inch

Severna Park, Anne Arundel:  0.75 inch

Herald Harbor, Anne Arundel:  0.70 inch

Cockeysville, Baltimore Co.: 0.65 inch

BWI-Marshall Airport:  0.62 inch

Bel Air, Harford:  0.55 inch

Taneytown, Carroll:  0.42 inch

The clouds, cold air and drizzle will be slow to depart the region, forecasters say. Today's showers should dissipate by 2 p.m. or so, although there will be some lingering risk until sunset. Temperatures will struggle to reach 60 degrees. We haven't quite reached 50 here at The Sun, at noon. The average high for this time of year at BWI is 70 degrees.

The cold front that crossed the region overnight has moved off the coast, but the trailing rain is taking its time. As skies finally begin to clear late tonight, radiation cooling will drop the overnight lows deep into the 40s. Western counties could see the 30s, and the weather service has issued frost and freeze watches for portions of western Virginia and West Virginia. "This could potentially damage spring crops sensitive to a freeze," forecasters warned.

Northwest winds Thursday will bring drier conditions, and sunshine will push daytime highs into the upper 60s - still cool for the season.  Low pressure  off the coast of Maine (see map; click to enlarge), and high pressure in the Ohio Valley will combine to make Thursday a windy one. Showers and thunderstorms become a factor again Friday and Friday night as new disturbances move by. 

For the weekend, Saturday is your best bet for outdoor activities, with  mostly sunny skies predicted, and a high near 70. Showers return on Sunday.

Posted by Frank Roylance at 11:29 AM | | Comments (0)
Categories: Forecasts

May 3, 2011

More showers, storms tonight with cold front

Forecasters are once again talking about the approach of a cold front, with rising chances for more showers and thunderstorms late Tuesday and overnight. Some of those storms could become severe, with a risk of damaging winds, large hail and an isolated tornado or two.

As if we haven't seen enough tornadoes for one month - four in Maryland last week at last check.

The chance of showers begins to climb after 5 p.m., according to National Weather Service forecasters in Sterling, Va.  Those chances rise to 80 percent overnight, with thunderstorm risks beginning between 10 p.m. and 2 a.m., and then more showers into Wednesday morning.

The NWS has posted a Hazardous Weather Outlook for today and tonight in Central Maryland, noting the potential for thunderstorms to become severe, especially along and west of I-95. There's also a Coastal Flood Advisory, as onshore winds combine with high tides to boost tidal maxima one to two feet above normal.

The cold front should push through the area late Tuesday, ushering in cooler temperatures, with highs in the 60s  through Saturday. Today's warmth - highs in the 80s - will be short-lived.  

The sun should return late Wednesday, with clear skies overnight into Thursday allowing radiational cooling that could take the lows deep into the 40s. High elevations to our west may need a frost or freeze warning. We'll see mostly sunny skies Thursday, and clear enough Thursday evening to watch a nice flyover by the International Space Station. Watch this space.

We could see some passing showers Friday. But Saturday looks great, with mostly sunny skies again, and highs near 70. Another disturbance on Sunday could bring a passing shower or two.

Posted by Frank Roylance at 10:32 AM | | Comments (1)
Categories: Forecasts

April 27, 2011

Rain risks increasing today, tomorrow

There were a few sprinkles on the windshield this morning, but we're likely to see more as the day - and night - progress. Forecasters out at Sterling are calling for isolated showers for Central Maryland this morning, increasing to a 30 percent chance after 4 p.m. The forecast includes a April showers"slight" risk of severe storms through tonight.

There's nothing on our rain gauge yet, and, with some luck, we'll get through the Schaefer funeral without everyone getting soaked.

The chance for showers and storms continues through the night. But the real show begins Thursday. The NWS is predicting showers and thunderstorms after 10 a.m. Thursday, gusty winds  and as much as an inch of rain possible in some locations. The rain chances are put at 80 percent as the cold front that's been pummeling the Midwest and the Mississippi Valley finally moves through.

The worst of today's rain appears headed for Washington and Allegany counties in Western Maryland. Forecasters have posted a Flash Flood Watch for those counties, including Hagerstown, Frostburg.

"Thunderstorms capable of moderate to heavy rain will develop tonight and tomorow morning and move through areas with nearly saturated soils. These storms could lead to flash flooding," the weather service said.

There's sunshine and milder temperatures in store for us behind the front. The forecast looks sunny right through the weekend, with highs mostly in the 70s.

(SUN PHOTO: Doug Kapustin, 2001)

Posted by Frank Roylance at 10:24 AM | | Comments (0)
Categories: Forecasts

April 26, 2011

More showers and storms before weather cools

Back in the saddle today after clearing 1,038 email messages that piled up while I was off. Heard tell of some stormy weather during my absence. And it looks like the storms and showers will stick AccuWeather.comaround for a few more days before a cold front later this week finally clears the air.

In the meantime, we're headed for another high in the 80s Tuesday, making this a three-fer. The instruments at BWI-Marshall reached 85 degrees on Sunday and Monday. There were no records; the record highs are now almost all in the 90s. 

But this is the first time we've had three straight days at 80 or higher since last Sept. 23-25.  We're about 15 degrees above the daily averages for Baltimore in the end of April. Feels like summer out there.

We may see 80 degrees again on Wednesday as high pressure and sunshine continue to keep the atmosphere stoked. That will also continue the risk of showers and thunderstorms all the way into Thursday morning. April 24 storm, James Willinghan

Increasing humidity on Wednesday will thicken the cloud cover, ahead of a cold front, forecasters say. The front may come with some locally heavy rains. High atmospheric moisture and ground saturated by the rains of the past couple of weeks could raise the risk of stream and creek flooding.

But despite the destructive weather this system has produced to our south and west, the risks of damaging storms in Central Maryland late Wednesday into Thursday are described by forecasters as "slight." But it's not all good news. Those storms that do form have the potential to produce damaging gusts and large hail, especially to our west.

High pressure moving in behind the front will produce a terrific Saturday, withy mostly sunny skies and highs near 70 degrees. Sunday looks nearly as good, but with more clouds and a risk of showers later in the day as the next cold front approaches.

(PHOTO: April 24 storm, from Elkridge, by James Willinghan. Used with permission.)

Posted by Frank Roylance at 1:30 PM | | Comments (2)
Categories: Forecasts

April 16, 2011

Travel delays likely Saturday in heavy rain

That's a cold rain falling outside this Saturday morning,. And it appears it's just the beginning. Forecasters AccuWeather.comare predicting 1 to 2 inches of rain in Central Maryland, with more just to our west.

The storm is expected to slow traffic on the region's interstates, and across a wide swath of mid-Atlantic airports. Not good news if you're headed out of town.

Here's's take on the powerful storm. This is the same system that has triggered violent tornadoes across the south, with numerous fatalities and tremendous damage.

For those in the Plains states, on the back side of the circulation, the storm has trigger heavy, wet snow.  The flakes have even covered the nest of the Decorah, Iowa eagles that have fascinated so many online viewers.

Here in Central Maryland, the National Weather service has posted a Coastal Flood Advisory, calling for high tides Saturday two to three feet above tide table predictions along the Western Shore of the Chesapeake. There is a Coastal Flood Watch for more of the same overnight.

And wait; there's more. A Hazardous Weather Outlook for the region calls for all of the above, and this:


Finally, there is a Flash Flood Watch posted for all of Maryland west of I-95, where heavy rain falling on wet or saturated ground will raise streams out of their banks:


Posted by Frank Roylance at 10:15 AM | | Comments (2)
Categories: Forecasts

April 14, 2011

Heaviest rain due west of urban centers

Here's the rainfall prediction from NOAA's Hydrometeorological Prediction Center in Camp Springs. It shows most of the heaviest rain due on Saturday will fall to the west of Baltimore and Washington. Many locations will see more than an inch, with some in line for 1.5 inches or more, especially in thunderstorms. (Click to enlarge.)

Posted by Frank Roylance at 3:38 PM | | Comments (0)
Categories: Forecasts

April 13, 2011

Sunny, warmer Thursday, 1-2" of rain possible Sat.

This slow-drip water torture should be thinning out this afternoon, giving way slowly to some clearing skies this evening. The best news is that Sterling is forecasting sunny skies for Thursday, Weekend stormwith highs in the upper 60s. Even Friday will bring some sunshine, but with cooler temperatures as winds swing to the east and bring in more moisture and clouds.

The wind shift will signal the approach of the next low, and the likelihood of some heavy rain and thunderstorms on Saturday. The storm comes to us from the Midwest, but the counter-clockwise circulation around it will draw wind and gobs of moisture off the Gulf and the Atlantic.

It will also be a slow-mover, providing more time for the rain totals to pile up. The NWS forecast allows for as much as 1 to 2 inches before it all ends on Sunday. The period of heaviest rainfall will be Saturday, lingering into Saturday night and possibly Sunday morning.

The NWS has issued a Hazardous Weather Outlook statement, noting the risk of heavy rain Saturday and the possibility of flash flooding as already-high streamflow rates are swelled by even more runoff. 

Skies will start to clear later in the day Sunday, becoming partly sunny, with highs around 60 degrees.  Monday looks nice, with the next chance of rain on Tuesday.

Keep the umbrella handy. Here's Prof. Jeff Halverson's take on the weekend storm. He's an associate professor of Geography and Environmental Systems at UMBC:

Continue reading "Sunny, warmer Thursday, 1-2" of rain possible Sat." »

Posted by Frank Roylance at 12:13 PM | | Comments (1)
Categories: Forecasts

April 12, 2011

Friday/Saturday rain could be heavy

Showers today, tonight and Wednesday could drop more than an inch of rain in some locations across Central Maryland. But forecasters are looking ahead to what could be some heavy rains late Friday into Saturday.

cherry blossomsOnce the low-pressure system darkening our skies today and Wednesday moves east and away from the mid-Atlantic coast, our skies will clear as high pressure moves in. Temperatures have been falling all night, and won't get much higher today than they are this morning. By tomorrow we'll be looking at highs again in the 50s. Sunshine returns Thursday, but the blue sky will be short-lived.

By Friday night, the high pressure will be moving off, and the next storm system will be cranking up over the Midwest. As that low intensifies, it will draw what forecasters are calling "copious amounts of Atlantic/Gulf of Mexico moisture" into our region. Sterling says it's still too soon to say precisely where the rain will be heaviest, or how much will fall. But you can plan on your Saturday being wet.

Sunday, at least, looks partly sunny and cool, with a high in the 50s.

Jeff Halverson, associate professor of georgraphy and environmental systems at UMBC, says the storm is a classic "cut-off" low.

"A cut-off is a large, cold, upper-level cyclonic vortex that has broken free from the westerly jet stream ...It's a bit of a rogue whirlpool, and it moves sluggishly, and can even become stationary overhead," he said. This particular cutoff will gain strength from a powerful surface low over the Great Lakes, and another low expected to develop over the mid-Atlantic.

"Because of the cold air aloft (an unstable atmosphere) and a good tap on Atlantic/Gulf of Mexico moisture in a southerly flow ahead of the front, heavy periods of showers w/embedded thunder are a good bet Saturday-Saturday night-Sunday AM." 

(SUN PHOTO: Frank Roylance, April 11, 2011)

Posted by Frank Roylance at 8:21 AM | | Comments (1)
Categories: Forecasts

April 10, 2011

Another Monday in the 80s, another record targeted

With a warm front moving north overnight, and warmer, wetter air pushing into the region from the south, forecasters say we can expect "another very warm Monday." 

The forecast high is 82 degrees for BWI-Marshall Airport. That's just 3 degrees below the record high for the date - 85 degrees, set in 1887. Dulles Airport in Northern Virginia is looking for a high of 84 degrees, which could threaten the record of 87 set for the date there in 1977.

Last Monday's forecast called for a high of 78 degrees. But the NWS folks out at Sterling, Va. regularly underestimate the warm-weather highs at BWI. So we guessed we would top that and threaten the record of 83 degrees for an April 4 in Baltimore. We did. The day's high at BWI was a record-breaking 86 degrees. It was 87 downtown for the Orioles' home opener.

NOAA/NWSSo we may well threaten the April 11 record of 85.

The setup is the same. Forecasters say the wedge of cold air that has kept us cool all weekend will be moving north overnight as a warm front. Southwesterly winds and increasing moisture will mean temperatures may turn and head higher well before dawn. That will raise dewpoints, bringing us some morning fog. Once that burns off and skies clear, the April sunshine will heat us up even more.

And, just like last week, there is a cold front expected to cross Central Maryland Monday evening behind the warm front. That will raise the risk of showers and thunderstorms, probably after midnight Monday night, with as much as a half-inch of rain. There's "slight" risk some of those storms will be severe in northeastern Maryland, capable of damaging gusts and large hail.

The same scenario last week brought a small tornado to northern Charles County and brief, but powerful wind gusts to parts of Southern Maryland.

Behind the front, forecasters say we can expect more seasonable temperatures again, with highs in the 60s and lows in the 40s for the balance of the week. Mid-week looks sunny, with rain chances returning Friday night into Saturday.

Posted by Frank Roylance at 9:26 PM | | Comments (0)
Categories: Forecasts

April 7, 2011

Risk of rain through Monday; then high of 80

Okay, so we were too gloomy yesterday. The NWS forecast called for "mostly cloudy" skies Wednesday and a high of 61, and we went with it. The day turned out to be a beautiful spring offering, with clear skies into the early evening, and a high of 65 in downtown Baltimore. Perfect.East warm-up

So today they're calling for "mostly cloudy" skies again, and a high of 65. And it looks beautiful out there around the State Penitentiary, which is all I can see from the newsroom window. So let's just call it a happy break from the cold and wet weather we've seen most days since the equinox, because the weekend - while there's a warmup coming - also looks pretty wet.

Forecasters out at Sterling have posted a seven-day forecast listing rain chances, unequivocal rain, likely rain and risks of showers for pretty nearly every day and night through Monday. Highs will sag back into the 50s Friday before climbing back to forecast maxima of 71 on Sunday and "near 80" on Monday.

The problem is a weak cold front that's forecast to stall near the Mason-Dixon Line. It's colder north of the front, and warmer south of the front. Washington should see highs in the 70s today. Light rain is possible late tonight, with more likely Friday as disturbances move along the stalled front, and again Saturday.

Things warm up considerably Sunday and Monday as the line moves north again as a warm front. Allergy seasonThe next cold front will be close behind on Monday, with thunderstorms possible as it passes by, trailing behind a low crossing the Great Lakes. Despite the name, temperatures are forecast to remain mild after the cold front goes past, with highs Tuesday and Wednesday predicted to reach the low 70s, under mostly sunny skies.

Speaking of mild spring weather, have you noticed the pollen counts for trees? They've reached "high" levels in the region this week. But then, if you have allergies, you didn't need anyone to tell you that. Come to think of it, my throat's been kind of scratchy... You?

Posted by Frank Roylance at 10:37 AM | | Comments (3)
Categories: Forecasts

April 6, 2011

Sunshine will fade today; gray and wet ahead

Pretty crisp out there this morning. Temperatures at BWI-Marshall Airport dropped to 34 degrees overnight, down 52 degrees from Monday's record high of 86. Had to scrape some ice and switch the car heat back on.

The bright April sunshine is nice, but sadly it's going to fade as the day wears on. Look for high clouds to move in as the clear, high pressure moves east and a weak disturbance to our north Rain delay Oriolesdrags a cold front this way. The northern counties could see a few drops of rain, but mostly we'll get just clouds with highs in the 60s Wednesday and Thursday.

UPDATE, 6 p.m.: Clearly, the cloud cover headed our way has been delayed, due now to arrive overnight. So we snuck in a fine day in spite of the earlier forecast. We deserved it. But the clouds are close. Earlier post resumes:

The clouds will keep overnight lows from dropping below the 40s, so we shouldn't have to scrape windshields again. The cold front (click map to enlarge) is forecast to dip south Thursday, bringing us rain chances Thursday night, increasing to 70 percent by Friday. Those of us who wind up north of the front will get a steadier rain, forecasters said. Those to the south will see a more scattered variety, with a chance for thunderstorms, and milder temperatures.

Groundskeepers at Camden Yards will be watching the skies as they try to squeeze in the Rangers' games.

Rain chances diminish to 30 percent for Saturday and rebound to 40 percent Saturday night. But they don't relent until Sunday. Forecasters predict "mostly cloudy" skies Sunday, with a high near 63 degrees. That looks like the outdoor day this weekend.

Still looking for a break in the weather? Hang on a while longer. Forecasters say disturbances moving along the stalled temperature boundary will mean a persistent 40 percent chance of showers through Monday. Schedule your mental health day for Tuesday which, at least from this distance, looks to be sunny, with a high of 72 degrees.

Posted by Frank Roylance at 10:12 AM | | Comments (2)
Categories: Forecasts

April 3, 2011

70s and breezy for Opening Day; storms by midnight

Fans headed to Camden Yards for the Orioles' home opener Monday can plan on temperatures in the mid-70s, with partly sunny skies for the hours they'll be in the stands. But the weather will be going downhill during the evening.

The National Weather Service said there is a 30 percent chance of showers overnight into Monday, so the ushers may need to wipe of the seats for you if the sunshine and wind haven't evaporated Opening Day Oriolesall the moisture by game time. 

But as the high-pressure center that brought us such welcome sunshine on Sunday moves out over the Atlantic Sunday night, it will be replaced by low pressure moving into the Great Lakes.

That will draw a warm front north during the day and, along with a strong April sun, will drive our afternoon temperatures into the 70s on strong southerly breezes. Some locations could see the upper 70s to near 80 degrees, and wind gusts to 30 mph.

The mercury should still be in the 60s at Camden Yards by the time the game ends. But a strong cold front approaching behind the warm air will begin to touch off showers and thunderstorms late in the evening, forecasters said.

The front should reach Baltimore and the I-95 corridor by midnight. Expect gusty, perhaps damaging winds with the front. Rain could be locally heavy in thunderstorms, with some risk of flash flooding.

The showers and storms could persist into early Tuesday. Daytime temperatures will hold in the 50s with strong breezes and gusts as high as 36 mph.

It will be sunnier, but not nearly as warm for the Orioles' second home game against Detroit, on Wednesday. The forecast calls for mostly sunny skies and highs near 60 degrees. 

(SUN PHOTO: Lloyd Fox, April 1, 2011)

Posted by Frank Roylance at 3:51 PM | | Comments (0)
Categories: Forecasts

March 31, 2011

Drizzle, rain, showers ... and a peek at the sun

The snowflakes that fell on the WeatherDeck Wednesday night melted away on contact, and forecasters say we might slip a few hours of sunshine into our day on Friday. And Sunday actually looks sunny, with a high in the mid-50s.

But that's about all the good news we can find in the seven-day forecast this Thursday morning. Most of the memo reads like some sort of cold, cloudy waterpark adventure: "Drizzle, then rain ... Spring BaltimoreChance of showers ... increasing clouds ... a chance of showers and thunderstorms ... a low around 36 ... mostly cloudy."

The problem is a series of low-pressure systems traveling across the region, and the wedge of cold air still being pumped into the northeast by that high over Quebec. If this were January (or, if we lived in New England), we'd be shoveling snow and ice instead of just longing for sunshine and green grass and blossoms.

Anyway, last night's bout of rain and sleet and snow has moved out to sea. The next low will bring us more rain late today and tonight, with as much as an inch of new rain possible by Friday morning.

Once THAT disturbance moves on to New England, forecasters say we'll get a brief glimpse of sunshine Friday afternoon before the NEXT one passes through with more showers after Saturday.

The sun should come back after that rain moves off Saturday morning. Highs could reach the mid-50s on Saturday before dropping back to the mid-30s overnight.

Sunday promises to be the best-and-only nice day of the entire stretch, with sunny skies and highs in the mid-50s, if the forecast holds up.

Enjoy it, because rain chances return Sunday night into Monday as the next storm system moves in. We could add thunderstorms on Tuesday as temperatures reach the upper 60s, briefly. Wednesday looks partly sunny from here, in the 50s. That's still cooler than the norms for Baltimore in early April. sees no satisfying end to the unseasonably cold weather.

Posted by Frank Roylance at 9:52 AM | | Comments (1)
Categories: Forecasts

March 30, 2011

More gray, cool and wet weather 'til Saturday

Just try to pretend you're in Ireland and maybe the next few days of cool, wet weather won't seem so bad. A handy pub, a crackling fire, and it won't seem nearly so dreary.

But it looks like we're stuck with at least three days of it. National Weather Service forecasters in NOAA/NWSSterling, Va. say we're in the path of two low-pressure systems that will bring rain, showers and drizzle to Central Maryland later today, and continue with more of the same into Saturday morning.

The good news is there is no longer any mention of snow in the local forecast, at least east of the Blue Ridge. Overnight lows will continue to drop into the 30s, but if there is any mixing of drops and flakes north and west of Baltimore and Washington, it shouldn't amount to anything.

UPDATE: 6:30 p.m.: Forecasters have reversed course, and are now calling for a mix of rain and sleet around Baltimore Wednesday evening, and rain and snow Thursday evening as temperatures dip to the mid-30s. But little or no accumulation is forecast. Earlier post resumes below:

The first round of rain is expected after 2 p.m. Wednesday, with as much as a quarter inch possible. Expect the same overnight, and still more drizzle and rain across the region Thursday as the second low-pressure system begins to take shape off the Carolina coast.

The new storm will bring more rain Thursday night, especially east of the mountains and north ofNOAA/NWS the Potomac. Up to a half-inch is possible with this one, forecasters say.

Rain chances continue on Friday, but there is also a mention of "partly sunny" skies in the forecast.

More rain is possible Friday night into Saturday before noon. But then, finally, we're due for a break. Sunday should be sunny, forecasters say, with a high in the upper 50s.

Sadly, there's more rain in the forecast for the early part of next week. Some of it may be heavy. April showers, and all.

Posted by Frank Roylance at 10:14 AM | | Comments (6)
Categories: Forecasts

March 29, 2011

NWS keeps tonight's snow to our west

Today's snow forecast map from the National Weather Service keeps all of tonight's expected snowfall well to our west. While the northern and western suburbs may see some flakes, any accumulations are expected to be in the higher elevations of the Piedmont and west of the Blue Ridge. But there may be more to watch by Friday.

High pressure hanging in to our north is continuing to keep air at the surface in Central Maryland unseasonably cold. Forecasters say the low-pressure system moving out of the Central Plains into the Tennessee Valley will begin to throw some high clouds our way later today, and start the rain by midday Wednesday.

Some snow could mix in by Wednesday evening after 9 p.m., continuing into Thursday morning. Then it should be all rain showers. Expect a chilly (40s) ands dank (east winds) day Wednesday in Central Maryland.

Accumulating snow is likely  along and west of the Blue Ridge Wednesday morning and again in the evening. Forecasters say higher elevations could see 2 to 4 inches. There is a Winter Weather Advisory out for Allegany County.

There's still a chance for rain or snow Thursday before noon in Central Maryland. And there's a coastal storm forecast by some models for Thursday night through Friday night. Here's how the forecasters at Sterling described it in this morning's forecast discussion:

"The intensification could be rapid ... Wintry precipitation would be west/north of the system. For now, rain/snow east of I-95 and all snow at higher elevations Thursday night. This will need to be closely monitored as plenty of Gulf/Gulf Stream moisture is available to the developing storm."

Posted by Frank Roylance at 10:24 AM | | Comments (2)
Categories: Forecasts

March 28, 2011

NWS: "Winter has not quite retired yet"

There are more snowflake icons on the seven-day forecast from the National Weather Service this week. A stubborn high-pressure system parked over Central Canada is pumping lots of cold air into the Eastern United States. Add a series of weak storm systems gliding along the jet stream NOAA/NWSjust south of the cold air and we get a risk of mixed rain and snow this week.

Central Maryland will have to shake off some clouds today as another storm system passes through Virginia, with some snow for the Carolina mountains. But northwest winds should eventually clear our skies, and we can look forward to more sunshine on Tuesday.

Daytime temperatures, however, will remain stuck in the 40s Monday. That's 10 to 15 degrees below the average for this time of year at BWI-Marshall Airport. Overnight lows will dip to the upper 20s Monday night, with colder readings away from the city centers and the bay. That's also 10 to 15 degrees below the norm.

NOAA/NWSMore sunshine on Tuesday is forecast to bring our temperatures into the low 50s. But the first storm system will send precipitation northeastward into our area late Tuesday into Wednesday. With cold air wedged against the eastern slope of the Appalachians, that raises the possibility of some frozen stuff.

Forecasters at the NWS regional forecast office in Sterling, Va. say we're in a better position this time to see some precipitation, and possible some snow, than we were on Sunday:

"Primary uncertainty lies in [the] influence of cold air near surface. Surface low pressure developing in coastal Carolinas ought to help maintain cool wedge at surface during this event."

"At the moment,  the possibility has increased for a significant snow accumulation for portions of the forecast area. Warm air near the surface likely to be quite shallow, so it seems likely that precipitation will change to snow in most locales eventually during the event. All models show snow during this period. But the uncertainty lies in amount and duration."NWS/NOAA

"SREF members [an ensemble of several forecast models] nearly unanimous in depicting snow in excess of 1 inch on Wednesday for most counties west of Blue Ridge. Half of the SREF members also show possibility of snow in excess of 4 inches on Wednesday. It does appear that winter has not quite retired yet."

After a break on Thursday, we're looking at a chance for more rain and snow Thursday night into Friday, and rain on Friday night.'s Henry Margusity is talking up a "big" Friday storm, with heavy, wet snow to our west and north, and "rain changing to snow" for the "big cities." No hint of that yet for us in the NWS forecast. 

Prof. Jeff Halverson, at UMBC's Jt. Center for Earth Systems Technology, sees nothing of the kind:

"This time of year, climatology argues strongly against snowfall in the Mid Atlantic east of the mountains; heavy snowstorms are possible in early spring across south-central Appalachians, but are quite rare. Not impossible here, but the odds really do stack up against anything more than a cold, rainy day." 

The weekend looks better, with some sunshine and more seasonable highs in the 50s. But it may be weeks before we see the really warm weather we're longing for.'s Paul Pastelok says this chillier pattern could hold on until May.

Posted by Frank Roylance at 10:14 AM | | Comments (2)
Categories: Forecasts

March 26, 2011

An inch or two at worst

UPDATE, 7:15 a.m. SUNDAY: We haven't seen a flake out on the WeatherDeck in Cockeysville, but the NWS is reporting light snow in Anne Arundel, including Annapolis, in Washington, D.C., and even Westminster. The CoCoRaHS Network is reporting a bit of snow to our south, too. The entry from Waldorf, in Charles County, is scarcely believable. A typo? Should it read 0.5 inch? Can anyone confirm it?:

Waldorf:  5.0 inches

Parsonsburg, Wicomico County:  3.5 inches

Salisbury, Wicomico County:  3.0 inches

Leonardtown, St. Mary's Co.: 1.0 inch

Brandywine, PG Co.:  0.9 inch

Bryans Road, Charles Co.: 0.5 inch

Easton, Talbot Co.: 0.1 inch  

Here's a snow report from the National Weather Service. And a snow map. I'd say the pre-treatment of the roads Saturday around Baltimore (earlier report below) was wasted.

UPDATE at 9:20 p.m. Saturday, from Sun reporter Jonathan Pitts:  The State Highway Administration started pre-treating interstate highways in the Baltimore area, where they treated I-70, I-695 and I-95, this afternoon, according to Lora Rakowski, an administration spokeswoman. Crews will be staffing all SHA maintenance stops and deploying to their routes at midnight Saturday, Rakowski added, to begin salt application as precipitation was expected to begin.

Here's the snow forecast for Central Maryland for Saturday night into Sunday: Not to worry. Should be more of an early-spring curiosity than a winter storm.

The Winter Weather Advisory out today calls for 1 to 3 inches to our south, encompassing no more than Charles, St. Mary's and Calvert counties in Southern Maryland. (Southwestern Virginia will see more):




Farther north, the National Weather Service is calling for about an inch. Here's the forecast map. Click to enlarge:

Posted by Frank Roylance at 2:58 PM | | Comments (3)
Categories: Forecasts

March 25, 2011

"Accumulating snow" expected overnight into Sunday

Central Maryland could see "accumulating snow" early Sunday as a low-pressure system moves out of the Gulf Coast states into the southern Appalachians. There's even an outside possibility suggested by some forecast models that Southern Maryland could see as much as 4 inches. But forecasters say that outcome "seems unlikely."

AccuWeather.comThis wintry weather in early spring comes as Washington, D.C. prepares for its annual cherry blossom festival, and trees across the region begin to bud and bloom. Willows, forsythia, bulbs are showing some color, and many other species seem ready to burst, Tellingly, tree pollen counts are also up.

The problem seems to be a stubborn high-pressure system over Quebec that keeps sending cold air south into the eastern states. It was 24 on the WeatherDeck in Cockeysville this morning.

Add a series of disturbances traveling along the jet stream at the southern edge of the cold air, and you get repeated bouts of cold rain and the occasional snowflake.  And it's not going away quickly. Here's's take.

Snow flurries could mix with sprinkles as soon as tonight, forecasters said, as a disturbance in the Central Plains states begins to move east. Sunny skies Friday morning will begin to cloud up, and winds will shift to the northeast as the low gets closer. There's a 30 percent chance we could seeFrost rain or snow showers before 10 Friday evening, forecasters said. Western suburbs and the higher elevations to our west could see a dusting.

The main event comes late Saturday into Sunday. After some clearing behind tonight's precipitation, forecasters expect temperatures by Saturday morning will drop into the mid-20s north and west of the urban corridor, with lows near freezing in the cities.

Saturday should be dry and partly sunny, but the next disturbance moves out of the Gulf states into the southern Appalachians Saturday night into Sunday. That will turn winds back to the northeast, adding relatively warm, moist air on top of the cold air at the surface - the recipe for snow in the winter months.

"Accumulating snow is expected Saturday night and Sunday," forecasters said. The forecast for Baltimore calls for snow to begin after 2 a.m. Sunday, continuing Sunday morning before changing to rain after 2 p.m. The overnight lows are expected top be in the upper 20s, recovering to a high of only 37 on Sunday. That's 20 degrees below the average for this time of year in Baltimore.

The most moisture will be to the south of Baltimore, but the coldest air will be to the north, making it difficult for forecasters to predict accumulations with any confidence.

Eric the Red, a professional meteorologist in Baltimore, parsed it this way on Thursday. He said several models predict "decent" snowfall in central and northern Maryland - 2 to 4 inches on grassy surfaces. Others put the same snow across northern Virginia and Central Maryland.

"I'm inclined to think that much of the region will see 1 to 3 inches of snow, with the lighter amounts in far northern Maryland" he said. "The heaviest precipitation at this juncture appears to be aimed ay northern Virginia. This snow - if it materializes - will not impact traffic, and I don't think you need to worry about shoveling it."

It won't be hard to break a record. The heaviest snowfall on record for Baltimore on a March 27 was the 0.4 inch that fell in 1924.

The unseasonably cold weather is likely to moderate slowly as the new week begins. Sunshine returns with high pressure Monday, and highs are forecast to reach the mid-50s - near normal - by Wednesday. More precipitation is possible on Tuesday night, but it's expected to fall as rain showers.

(SUN PHOTO: Frosty morning, Frank Roylance)

Posted by Frank Roylance at 10:35 AM | | Comments (6)
Categories: Forecasts

March 24, 2011

Skies will clear today; snow possible Sunday a.m.

The northeast winds that have been bringing us all this cold, damp Atlantic air are expected to shift to the north today, and the switch will begin to dry us out, finally.

Look for skies to begin to clear by mid-day, with sunshine returning in the afternoon and clear skies by sunset, forecasters say. Friday and Saturday, high-pressure will dominate, and we should be able to recharge our solar batteries for a few days before the next round of precipitation.

Spring snowWhich brings us to the cold, and the snow. Daytime temperatures, sadly, will remain in the chilly 40s, slipping below freezing at night well into next week. With trees and plants starting to wake up and bud, the weather service is urging us to "take any necessary agricultural precaution for the freezing temperatures tonight."

The airport lows Thursday night/Friday morning are forecast to reach 27 degrees. That's about 10 degrees below the average for this time of year, but well short of the records, which are closer to 20 degrees.

The interesting stuff comes Saturday night into Sunday morning, as another low-pressure system moves out of the Tennessee Valley and crosses the Carolinas. That will bring us precipitation, along with northerly winds dropping overnight lows to near 30 degrees. It's likely to mean a changeover to snow before it switches back to rain late Sunday morning. Forecasters put the chances at 50 percent for snow Saturday night, and 60 percent for a rain/snow mix Sunday morning.

"There might be light accumulations of snow during this time," forecasters said in their morning discussions. But forecast models differ on how much.

I can't see this as anything to worry about. With any luck, it will be winter's last gasp. Good. With the trees in bud, I'm done with winter. You?

(SUN PHOTO: Amy Davis, 1997)

Posted by Frank Roylance at 10:20 AM | | Comments (3)
Categories: Forecasts

March 22, 2011

Rain likely tonight through Thursday morning

A stalled cold front to our south puts us in line for a stretch of cold and dreary weather ahead.

Forecasters at the National Weather Service in Sterling, Va. say we can expect mostly gray skies today, with a high near 60, although some sunshine does seem to be breaking through.

Daffodil springRain moves in late this evening. A low-pressure system moves along the front tomorrow, bringing us an 80 percent chance for more rain, with thunderstorms possible Wednesday afternoon. The high temperature on this (colder) side of the front will stick near 50 degrees as counterclockwise winds around the low bring us east winds off the Atlantic. We could see up to a quarter-inch of new rain. Just south of the front, parts of Virginia could see the 70s.

The risk of showers and thunderstorms continues into the late evening Wednesday, forecasters said, with another quarter-inch of rain possible.

Thursday starts out with some risk of more showers, and western counties could see some snow Rain March Baltimoremixing in as the low moves out and cold, Canadian air works in behind it. But our skies should begin to clear late in the day.

Look for some cold nights behind the front, with temperatures falling into the upper 20s at BWI Thursday night. Friday looks sunny, but little warmer with a high near 49 degrees - almost 10 degrees below the average for BWI at this time of year.

The next (weak) storm system moves in on Friday night into Saturday, bringing more chances for a wintry mix to our west, and more clouds on Saturday. Daytime temperatures at BWI on Saturday will stall in the 40s, and fall back to the 30s overnight. More rain overnight into Sunday is possible, with lows again in the 30s, with a risk of more-widespread mixed precipitation.

The sun is due back on Monday, but temperatures will remain cool.

(SUN PHOTO: Jed Kirschbaum, March 2003)

Posted by Frank Roylance at 11:12 AM | | Comments (0)
Categories: Forecasts

March 21, 2011

A wet week, with a chance for a flakey finish

Woke up this morning thinking someone was dragging furniture across the WeatherDeck. But flashes of light on the ceiling quickly told me it was thunder. It was an odd way to wake up on a March morning. But, considering the clock radio failed to do its job today, my favorite teacher and I were grateful for the noise.

At least we're not in northern New England, where they're getting snow today.Rain probability Maryland

It appears we're looking at a pretty wet week. Forecasters at the National Weather Service's regional forecast office in Sterling, Va. say we should expect Monday's mid-day lull to yield after 3 p.m. to more showers and possibly thunderstorms as the approaching cold front moves by.

The showers could persist until midnight, but Tuesday, at least, promises a little sunshine, with highs near 60 degrees.

That may be it for the sun until Friday. The cold front is expected to stall to our south, becoming a set of rails for a series of low-pressure systems to ride through on. They will bring us more showers and thunderstorms Wednesday, Wednesday night and Thursday before ending in the morning hours.

Friday is forecast to be sunny, but unseasonably cool, with a high in the upper 40s. Then, another storm system is due to cross the southern mid-Atlantic area Friday night into Saturday. And with the lows expected to fall to near freezing Friday night and again on Saturday night, NWS forecasters said some of the precipitation each night could mix with snow north of Washington, D.C. before changing over to all-rain:

"Both of these weekend features appear to be limited to light precipitation, but warrant close analysis in the coming days."

Posted by Frank Roylance at 10:46 AM | | Comments (0)
Categories: Forecasts

March 18, 2011

Enjoy today; cooler, wetter ahead

Today we'll enjoy the balmy temperatures, and the weekend will be pleasantly sunny, but cooler. From there, however, the weather goes downhill, with a series of cold fronts next week, with rain chances and highs mostly in the 50s.

Forecasters continue to call for highs Friday in the 70s. The folks at WJZ are still looking for things to top out at 77 degrees. The National Weather Service is calling for 74 at the airport. We've already reached 70, at noon, at The Sun's weather station, at Calvert and Centre streets.

The mild First bulbsweather comes courtesy of west winds that are coming over the Appalachians and compressing as they flow down the eastern slope. And, as anyone who has ever filled a SCUBA tank knows, when you compress a gas, it gets hot.

The breath of spring goes away later today when a low pressure system over southern Canada drags a trailing cold front across our region. Forecasters say that will drop temperatures into the 50s for the weekend, but it will also clear the skies. So we can look forward to lots of sunshine, and starry skies at night.

We should have a nice evening to watch the perigean full moon rise Saturday.

By early Monday morning we'll start to feel the effects of the next low coming off the Great Lakes. That will bring us a chance for a little rain overnight into Monday and more showers are possible during the day Monday, especially in the northern counties.

High pressure moves back in behind the low on Tuesday, with a sunny break and a high in the mid-60s before the next system rolls in. Low pressure moving this way from the Central Plains will raise our rain chances again Tuesday night into Wednesday and Thursday. But forecast models can't sort all this out very well yet. So stay tuned.

(SUN PHOTO: Frank Roylance)

Posted by Frank Roylance at 11:48 AM | | Comments (0)
Categories: Forecasts

March 16, 2011

Clouds will clear slowly; warmup ahead

The cold front has passed, but the clouds linger on this (Wednesday) morning. Forecasters promise the low deck of gray will begin to break up later today, and clear out overnight. We're already seeing some rays downtown at 11 a.m.

That will set us up for a terrific couple of days as high pressure builds into the region, sunshine does its job and temperatures climb into the 70s by Friday.

We got a fair amount of rain overnight. We're looking at 0.62 inch on the gauge here in The Sun's weather bunker, at Calvert and Centre streets. BWI-Marshall recorded 0.60 inch, bringing the month's total to about 4.3 inches. St. Mary's and Calvert counties and the Eastern Shore seem toMarch buds have caught the heaviest rains. Here are some totals from the CoCoRaHS Network:

Leonardtown:  1.09 inches

Park Hall:  0.92 inch

Prince Frederick:  0.83 inch

Easton:  0.83 inch

White Marsh:  0.73 inch

Severna Park:  0.72 inch

Once the high pressure builds in and the skies clear, we'll all have a better outlook. And as the high begins to move offshore on Friday, we'll get into some west winds, and that will to push temperatures well above the seasonal averages.

The folks at WJZ are expecting a high of 77 degrees in Baltimore on Friday, according to their forecast this morning in our print editions. The National Weather Service is calling for 73 degrees at the airport. The average high at BWI for a March 18 is only 55 degrees. So we're looking at a maximum 20 degrees above the norm for the date. Sweet.  

The next cold front will pass through late Friday into Saturday. There's a small chance of some overnight rain with it. But the weekend still looks sunny, with highs near 60 degrees. And the nice weather is likely to continue into the beginning of next week - the first week of spring.

(SUN PHOTO: Jed Kirschbaum, March 24, 2009)

Posted by Frank Roylance at 10:49 AM | | Comments (1)
Categories: Forecasts

March 15, 2011

New rain not expected to raise flood concerns

Despite the heavy rain late last week, and the high water remaining in some rivers and creeks across the region, forecasters don't expect new flood issues with the rain due overnight into Wednesday.

The National Weather Service is predicting a three-quarters to one inch of rain tonight and Wednesday morning. That would bring the month's total at BWI-Marshall Airport close to 4.5 Flooding Baltimoreinches, well over the 3.93-inch average for March, with two more weeks to go.

But, forecasters said, this amount of new precipitation, "over the course of about a 12-18-hour period is not expected to bring area rivers back to bankfull or minor flood stages."

Last week's rain topped 3 inches in many spots north of Baltimore. It brought minor flooding to the Monocacy, Potomac and Susquehanna Rivers in Maryland, and inundated numerous low spots around the region, closing roads and detouring traffic. Some business along the Jones Falls in Baltimore were evacuated.

The new rain is coming with a storm brewing Tuesday in the Tennessee Valley and moving in ourRain Baltimore March direction. Increasing clouds will begin to drop light rain here by evening, and rain rates will increase overnight, forecasters said. It should end by noon in the Baltimore area.

Once the storm clears out, we can look forward to sunny skies through the weekend, with a high of 74 on Friday before another, dry, cold front passes by during the weekend and drops highs back to the 60s.

(SUN PHOTO: Jerry Jackson, March 10, 2011)

Posted by Frank Roylance at 11:05 AM | | Comments (1)
Categories: Forecasts

March 14, 2011

After the clouds and rain Weds., 74 on Friday

We always look forward to Fridays, but this week there's an added bonus - a forecast of partly sunny skies and a high of 74 degrees. That would be our first foray into the 70s since Feb. 18, and only our third day this year with highs that warm.

So if you have a day off due, and you want to hit the trail, or the links, or the park, Friday looks like your day.

Spring sunshineBut first we'll have to deal with another round of rain late Tuesday into Wednesday, and highs no better than the 50s. The clouds start moving in from the north later today. Showers may start to break out Tuesday afternoon, picking up overnight and leaving a quarter- to a half-inch before ending sometime Wednesday morning.

That rain will come on top of the 3.69 inches already this month, and would put us close to, or over the average rainfall for March, which is 3.93 inches at BWI. 

The storm is brewing today (Monday) in the Mississippi Valley, and will begin increasing our cloud cover in the next 24 hours as the high-pressure system that brought us fine weekend weather moves east.

Once the high is offshore on Tuesday, the rain will begin moving in from the southwest. Baltimoreans can expect the showers to start after 3 p.m. Tuesday, picking up overnight and ending by noon Wednesday, forecasters say.

Then the sunshine returns, and temperatures climb toward the 74-degree high forecast for Friday. Another cold front slips by late Friday, dropping weekend highs back into the more seasonable 50s. But the sunshine should remain, if forecasters have it right. 

The spring equinox arrives on Sunday, marking the official start of spring.

(SUN PHOTO: Kenneth K. Lam, March 2008)

Posted by Frank Roylance at 10:56 AM | | Comments (0)
Categories: Forecasts

March 9, 2011

Dry winter yields to gusher of rain

Central Maryland is in for a gusher of rain overnight and throughout the day Thursday as a potent storm system moves out of the Gulf states with a heavy load of Gulf and Atlantic moisture.

On top of rainfall that could total 3 inches before the storm ends Friday morning, forecasters said persistent winds from the east and southeast will pile up high tides on the bay Thursday, two to three feet High waterabove normal.

The National Weather Service Wednesday posted Flood Watches for interior counties in anticipation of the heavy rains, and Coastal Flood Advisories for the Western Shore of the Chesapeake.

"The heaviest rain is going to occur toward the afternoon and into the evening,” said Steve Zubrick, science and operations officer at the National Weather Service’s regional forecast office in Sterling, Va.

"That’s going to fall on ground already saturated from last weekend’s rainstorm. Streams and creeks are going to rise pretty rapidly. Hopefully people will heed their senses, and heed any signs put out by local authorities, and not drive around any barricades,” he said. “I think [Thursday] afternoon will be quite a challenge for commuters, in places.”

Flood Warnings were already posted for the Monocacy River near Frederick, on Thursday. The river was forecast to rise to 19.8 feet by mid-afternoon. That's almost 5 feet above flood stage, and further rises are possible, forecasters said. Flood Warnings were also posted for the Potomac River at Point of Rocks and Harper's Ferry, and Conococheague Creek at Fairview  in Washington County..

In Baltimore, public works officials appealed to residents to clear trash from storm drains before the heavy rains start, and to report those they can't clear to the city's 311 service line. "Keeping them clear of trash and debris is crucial in preventing localized flooding," officials said in a statement.

The new rain could amount to nearly a month's worth in just 30 hours. It comes on the heels of 1 to 2 inches of rain on Sunday. That rain soaked the ground and filled streams, and forecasters said that increases the risk of flash flooding Thursday and Friday as the new precipitation begins to run off.

With this storm, Zubrick said, “we have a connection to the Gulf of Mexico, so that moisture is being pulled up into our area, and focused in our area, especially in the afternoon and evening. … And with the low-pressure system expected to go west of the Baltimore area, a prolonged period of east and southeast winds are going to pile up water in the bay … so we’re looking at coastal flood issues.”

"Talk about a change of plans in a short period of time," exclaimed another forecaster in AccuWeather.comWednesday's online discussion from Sterling. "Last week I was worried about the possibility of a very bad wildfire season this spring. But that worry has rapidly turned into concerns over flooding."

The rain caps a long period of relatively dry weather for Central Maryland. Baltimore has seen below-average precipitation every month since October. The winter has also produce only 14 inches of snow at BWI-Marshall Airport. That's four inches below  the long-term average there, and more than five feet less than last year.

The new storm was deepening Wednesday over the Gulf Coast states, and the counter-clockwise spin around the central low was driving very moist air from the Gulf and the Atlantic into the eastern states. There were flood watches, warnings and advisories in place from Louisiana to upstate New York in anticipation of the storm's passage. 

A mixture of light rain, sleet and snow was already falling Wednesday afternoon in the higher elevations of Maryland's western counties.  Rain was expected to start falling east of the mountains late in the day, becoming heavier overnight ahead of a cold front trailing the low. 

One to two inches of rain was expected at BWI during the day Thursday, possibly accompanied by thunderstorms. A half- to three-quarters of an inch more was expected Thursday night, ending early Friday. 

"By the time the front clears the area Thursday night, up to 3 inches of rain will be possible," the weather service said. "You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding occur."

The forecasts look great for Friday and through the weekend, with sunshine and highs in the 50s to near 60 degrees on Saturday. 

(SUN PHOTO: Andre Chung, 2006)

Posted by Frank Roylance at 2:08 PM | | Comments (0)
Categories: Forecasts

March 8, 2011

Hard rain due Thursday; Flood Watch posted

Today looks fine, with sunshine and highs near 50 degrees. And the weekend looks great, with more sunshine and highs in the 50s beginning on Friday. But in between, like the great Greenwich Village forecaster Bob Dylan said, it's a hard rain a-gonna fall - as much as 3 inches in some locations.

The National Weather Service regional forecast office in Sterling, Va. has posted a Flood Watch from Washington County in the west to Cecil County in the east, and reaching as far south as NOAA/NWSPrince George's and Anne Arundel counties.

In effect from Wednesday evening through Thursday evening, the Watch for the Baltimore region predicts as much as 3 inches of rain could fall in some locations as a slow-moving cold front approaches the region, and takes its sweet time moving off to the east.

The storm is already gathering strength in the Central Plains states, and is threatening the lower Mississippi Valley with severe thunderstorms, hail, destructive winds and even tornadoes late today. Even the Mardi Gras celebrations in New Orleans could be overtaken by storms late tonight.

Baltimore's forecast calls for rain chances to pick up after 1 p.m. Wednesday, becoming moderate to heavy after 10 p.m., with up to a half-inch possible before daybreak Thursday. More rain, heavy at times, is in the works for Thursday, with new amounts of 1 to 2 inches. Thursday night add to the total - as much as three-quarters of an inch more - before it ends early on Friday.

NWS: "The forecasted rainfall amounts likely will cause flooding of low-lying areas, as well as cause small streams and creeks to rise out of their banks. The runoff would then create significant rises on area rivers."

The flood risk is made more likely by the heavy rain that fell Sunday, and which is still making its way down the state's rivers and streams. Saturated soils will not be able to absorb as much of the next storm as they managed to soak up over the weekend.

Cold air sweeping down from the north around the backside of the departing low on Thursday night could set off some snow in the higher mountain elevations. Here in the lowlands, we can expect mostly sunny skies behind the storm, with seasonable highs in the 50s for the weekend. 

Posted by Frank Roylance at 10:53 AM | | Comments (1)
Categories: Forecasts

March 7, 2011

Sunshine until rain returns late Wednesday

Noticed a few cars during the commute this morning that had some snow on their hoods and roofs. We had only a sprinkle of flakes, or sleet, on the WeatherDeck. But some locations across Maryland really did get measurable snow overnight as the rainstorm pulled away and dragged some very cold air down from the north behind it.

New England snowstormThe National Weather Service is reporting 2.5 inches on Frostburg, Md. The highest totals were in West Virginia, topped by 6.7 inches on Bayard, Grant County. None of that, of course, compares with the foot or more from the same storm system, recorded this morning in portions of northern New England and northeastern Canada ( map, left; depths in centimeters).

Around here it was just rain, falling, it seemed, in a series of heavy showers, interspersed with drizzle. As predicted, the amounts were typically in the 1-to-2-inch range. But some locations in Harford and Montgomery counties topped 2 inches. Here's a sampling:

Gaithersburg, Montgomery County:  2.38 inches

Somerset, Montgomery County:  2.3 inches

Darlington, Harford County:  2.25 inches

Emmittsburg, Frederick County:  2.0 inches

Glen Burnie, Anne Arundel:  2.0 inches

Reisterstown, Baltimore County:  1.35 inches

Pimlico, Baltimore City:  1.25 inches

Here are some more rain totals from the CoCoRaHS Network. There is a Flood Watch up this morning for the Monacacy River in Frederick County as the heavy weekend rains continue to drain off. Only minor flooding is being reported. 

If you liked Sunday, you'll probably like Thursday, too. That's when forecasters expect the nextBulbs rainy cold front to pass through Central Maryland. We'll have sunshine and seasonable temperatures until then. And look for more gusty weather today.

But by Wednesday, a storm brewing in the Great Plains will begin to influence our weather. Like the weekend storm, this one will begin by dragging more warm, moist air up from the Gulf in the broad, counter-clockwise flow around the low. That will increase our cloud deck on Wednesday and raise our rain chances during the afternoon.

During the overnight period from Wednesday into Thursday, the forecast boosts the predictions to "moderate rain." But, like we saw on Sunday, that comes with some periods of heavy rain, as well. More stream flooding is possible.

The cold front finally moves through the area sometime on Thursday, followed by a rush of cold air out of the northwest - around the backside of the low. Once again, as we saw this morning, that could mean some snow in the mountains into Friday morning.

The weekend, at least, looks sunny and mild for the moment, with highs in the 50s.

(SUN PHOTO: Frank Roylance)

Posted by Frank Roylance at 11:26 AM | | Comments (0)
Categories: Forecasts

March 4, 2011

Sunday storm could drop 1-2" of rain

The good news is that we will avoid the snow and ice headed for the Great Lakes and northern New England this weekend. But forecasters out at Sterling are giving us a 100 percent chance for heavy rain on Sunday as the next cold front pushes through.

Saturday may be deceptively pleasant as the weather gods wind up to deliver the Sunday deluge. High temperatures will climb to the upper 50s. Skies will be mostly cloudy, but that leaves open the possibility of some sunshine peeking through. So if you have outdoor cleanup plans this AccuWeather.comweekend, get out there on Saturday.

Light rain begins to move in to the region late on Saturday, with overnight lows only in the mid-40s. Low pressure moving along the cold front will begin to spin up on Sunday, and AccuWeather's Henry Margusity is hinting at some potentially severe weather with a squall line moving through eastern Virginia and North Carolina and the Lower Eastern Shore.

Here in Central Maryland, National Weather Service forecasters are calling for as much as 1 to 2 inches of rain Sunday as the cold front approaches, and more Sunday night. Watch the forecasts for Flood Watches. There are none up yet (except in Garrett County), just a Hazardous Weather Outlook for now. But that kind of rain could send streams and creeks out of their banks. If you're in a flood-prone location, keep an eye on the water.

Behind the cold front, there could be some rain and snow mixing briefly north and west of the cities, and snow in the western mountains. Most likely, though, we'll just get a cold and breezy night on Sunday.  Next week gets sunny again, forecasters say, with seasonable highs and sunshine until the next potent cold front arrives at mid-week with more rain and bluster.

Posted by Frank Roylance at 11:13 AM | | Comments (2)
Categories: Forecasts

March 3, 2011

Weekend warmup comes with lots of rain

Temperatures dropped to 22 degrees out on the WeatherDeck in Cockeysville this morning, and to 25 here at The Sun's weather station, at Calvert & Centre streets. The low at BWI-Marshall Airport was also 25 degrees, which is 5 degrees below the 30-year average there.

There is a warmup on the way. As this cool, clear and very dry high-pressure system drifts off the East Coast tonight, we'll come into the return flow from the south. That will bring daytime highs to the 50s Friday and Saturday. But it will also bring thickening clouds, and light rain by Saturday as a cold front approaches from the west.

The light rain will increase to moderate or even heavy amounts Saturday night and Sunday as more moisture moves north and runs up over the colder air. We could see an inch or more of rain. And forecasters at Sterling say that could cause streams and creeks to rise out of their banks.

Coastal areas, too, could see some minor flooding as a new moon combines with persistent onshore winds to drive high tides above normal levels.

More seasonable temperatures and sunshine return early next week. The next chance for rain comes Wednesday. As the (clickable) Drought Monitor map above shows, we can still use more. 

Posted by Frank Roylance at 10:32 AM | | Comments (0)
Categories: Forecasts

March 2, 2011

Winds raise fire hazard today, cold tonight

Another gorgeous, late-winter day in Baltimore today, with sunshine and forecast highs near 60 degrees, well above the average. But low pressure moving across Quebec will mean breezy conditions in Central Maryland and an enhanced danger of wildfires.

The National Weather Service's regional forecast office in Sterling has issued a Special Weather Statement for the counties in Central Maryland, noting the fire danger. Winds will rise to 10 or 15 mph late this morning, with gusts to 20 or 25 mph. Low relative humidity and low fuel moisture add to the risk. So crush those smokes.

Once the barometer turns late today, winds will shift from the west to the northwest. That will bring AccuWeather.comin much colder air. The overnight low forecast for Baltimore is just 23 degrees, with teens in the normally colder suburbs - all well below the norms.

UPDATE, 5:15 p.m.: The Baltimore Health Department has declared a Code Blue cold weather alert for Wednesday night. Shelter hours will be extended, and outreach workers will check on vulnerable residents. 

The cold snap will begin to turn around on Thursday as the high moves east and winds moving clockwise around that high swing around to the south again. Temperatures will remain below normal on Thursday, with a forecast high of just 40 degrees. But things will pick up from there as warmer, wetter air begins to move north.

Light precipitation should show up late on Friday. The western mountains could see some snowflakes. By Saturday the rain will become heavier as a storm system moves into the Appalachians from the Southern Plains, forecasters said. We may even hear some thunder Saturday night or Sunday. And rains could become moderate to heavy at times.

The rain will wind up with the passage of another cold front late Sunday or Monday. Forecasters say there may even be a brief period of snow as colder air moves in. But they don't expect any accumulation.

Clearly, we still have a way to go before we shake off this winter entirely.

Posted by Frank Roylance at 10:38 AM | | Comments (0)
Categories: Forecasts

March 1, 2011

March begins with sunny week, showery weekend

Now that we've put the gray, drippy weather behind us, and fresh, dry Canadian air has moved in behind yesterday's cold front, we can enjoy some sunshine and pleasant late-winter temperatures.

Forecasters out at Sterling are calling for highs in the 50s for the rest of the work week, with the exception of Thursday, which will turn a bit colder after the passage of a dry cold front Wednesday evening. The mildest day looks to be Wednesday, with a forecast high of 58 degrees. Sterling thinks some spots will poke into the 60s. 

There will be plenty of sunshine, and starry nights, too. The fly enters the ointment for the weekend, March sunshine in Baltimoreas warmer, wetter air moves north into our region Friday and Saturday. That could produce showers by Saturday, as temperatures warm again to near 60 degrees. The rain chances will lop over into Sunday, as well. Monday is forecast to be sunny, with a high near 51 degrees.

Temperatures are then expected to turn colder next week, with below-average highs

In the meantime, February has ended. Finally. For a short month, it seemed like it would never end. Temperatures averaged 3 degrees above the 30-year norm, moderating what had been an especially cold winter during December and January. It was also dry, with just 2.69 inches of precipitation. That's .33 inch below the average, continuing the dry period that began in October. Dry weather is a trait of La Nina winters in the Southeast, and we seem to have caught the northeast corner of that.  

Wind made more news in February than snow. We had just 2.5 inches of snow at BWI. But the winds on Saturday, Feb. 19, averaged 55 mph, with a peak gust to 60 mph. The National Weather Service forecasters in Sterling said that was the windiest day at Baltimore in at least the last 10 years. They had not checked further back than that.

One other thing... Do you have any questions about the weather or backyard stargazing? As part of our new, expanded print weather page, we are now posting weather comments seven days a week, up from four. That's a lot of space to fill. Send me your questions and see your name in old-fashioned ink!  

(SUN PHOTO: Barbara Haddock Taylor, Mar. 9, 2010)

Posted by Frank Roylance at 10:23 AM | | Comments (0)
Categories: Forecasts

February 28, 2011

Showers, T-storms as cold front passes

Showers, thunderstorms and the possibility of some violent weather are all on the menu today as a cold front crosses the state.

The National Weather Service issued a Severe Thunderstorm Warning for parts of Prince George's and Anne Arundel County and points south until 1:30 p.m. as a potent storm moved through the NOAA/NWSarea at 50 mph. Damaging winds up to 60 mph were possible.

The wind and rain were already causing power outages among BGE's customers in Central Maryland. Almost 3,800 customers lost power. All but a few hundred has been restored to service by 2 p.m. 

Central Maryland was advised in a Hazardous Weather Outlook that thunderstorms moving along the front this afternoon and tonight could produce damaging winds and isolated tornadoes. Counties from PG south were under a Tornado Watch until 4 p.m.

As much as three-quarters of an inch of rain is possible in some locations as the front goes by.

Elsewhere, in the meantime, we've been seeing some scattered showers and threatening skies. High temperatures Monday could reach 70 degrees, forecasters said. But the thermometer at The Sun had barely made it to 61 degrees by 1:20 p.m.

Once the front goes by, we'll drop down to the low 30s overnight, with highs on Tuesday only expected to reach the upper 40s. But the sun will be back as high pressure moves in behind the cold front. Daytime highs will be closer to the seasonal norms for Baltimore. The overnight lows will drop into the 20s.

The clouds return late in the week, with rain due on Saturday. Skies should clear by late Sunday afternoon, forecasters said. 

Posted by Frank Roylance at 1:06 PM | | Comments (0)
Categories: Forecasts

February 21, 2011

Overnight snow could drop 5-8 inches

UPDATE 3:10 p.m.: The Winter Storm Watch is now a warning for Carroll; Central and Eastern Allegany; Extreme Western Allegany; Frederick; Harford; Northern Baltimore; Washington.


And the advisory for Anne Arundel; Howard; Montgomery; Southern Baltimore has been upgraded to a warning. 


UPDATE, 10 a.m.: A Winter Storm Watch has been issued beginning at 9 p.m. for the northern counties, including Frederick, Carroll, northern Baltimore and Harford counties. Forecasters say 4 to 6 inches of snow are possible overnight in the Watch area.


Here's the updated (clickable) forecast snow map:

Weather Service had predicted 1 to 3 inches of snow overnight at BWI-Marshall Airport as a pair of low-pressure systems move through the region. The precipitation will start as rain, become mixed in the wee hours of Tuesday as temperatures drop behind the first low, then change to snow before ending during the rush hour.

Here's how Eric the Red saw it last night:

"Over the weekend, models did everything imaginable... no storm, all rain, all snow, and now back to a north to south changeover.  I think I'll stick with 2 to 5" on grassy surfaces for central and northern MD... and once you get down toward Annapolis and DC, the question of when (and if) the changeover occurs becomes fuzzier.  I would suspect that unless the cold air really pushes in fast, locales south of Baltimore will struggle to get more than an inch or two."

Here, on the jump, is how he sees it this afternoon:

Continue reading "Overnight snow could drop 5-8 inches" »

Posted by Frank Roylance at 8:29 AM | | Comments (30)
Categories: Forecasts

February 18, 2011

Snow chances Tuesday morning

Sure, it was 74 degrees at BWI-Marshall Airport this afternoon (and at The Sun's weather station downtown). But this is not spring.

Snow forecast TuesdayThe National Weather Service forecasters out at Sterling, Va. are calling for a 30 percent chance of snow Monday night into Tuesday.

Eric the Red is talking snow, too:

"Cold front comes back thru Monday evening, setting the stage for a very interesting Monday night and Tuesday morning.  As the front pushes south, a low will move east along the front.  This is all about timing... If the front gets too far south as the storm tracks east along it, we'll be cloudy and cold and dry.  If the storm moves too quick, the front will be too far north and we'll get rain. 

"Or it could be third bowl of porridge... where the front gets far enough south to get cold air in the region but is far enough north to allow the moisture from the storm to fall as snow or sleet ... So,  chance of mixed [precip] developing Monday night... and changing to snow from north to south.  I'll pass along a better estimate later... but a prelim look is 2-5" on grassy surfaces."

Two to five inches!?! Five inches would make it the second-biggest storm of the season. But if it fails to stick on pavement, we can handle that.

Posted by Frank Roylance at 4:20 PM | | Comments (2)
Categories: Forecasts

Hold onto your hat; high wind watch up tonight

Sounds like a wild weekend ahead, with highs in the 70s Friday afternoon, gusts to 50 mph overnight into Saturday, and some whispers about rain and snow Monday into Monday night. Ready? Here goes:

Wind gusts SaturdayThis morning's overcast skies will burn off and forecasters say skies should become at least partly sunny Friday afternoon. That will help bring temperatures into the 70s across much of Central Maryland. The high at BWI-Marshall on Thursday touched 71 degrees. That gave us an average temperature for the day of 56 degrees, which was 20 degrees above the long-term average for the date.

The forecast high for Friday at BWI is 73 degrees. Sterling often shoots low on our warm days, so don't be surprised if we top that.

The real excitement comes late in the day and overnight. The warm air rushing into the region from the southwest and west is doing so ahead of an approaching cold front. The front is draped southward from a strong low-pressure system crossing the Great Lakes today. High winds Baltimore

As the front approaches and passes through, it will be mostly dry. But winds will pick up. A lot. Sterling is predicting sustained winds in northeast Maryland from 20 to 30 mph, with gusts to 50 mph. Some locations, especially the Appalachian ridges, could see gusts to 60 mph.

BGE is anticipating more power outages from the wind storm. They said Friday the winds "could very likely cause trees and tree limbs already weakened by last month's heavy, wet snow and wind, to fall onto power lines and other electric delivery equipment, causing power outages. BGE has more than 650 employees and contractors on stand-by for restoration work..."

UPDATE: 5 P.M.: The weather service has also issued a High Wind Warning from 5 a.m. to 9 p.m. Saturday, from Allegany County east to Harford, and  south to Prince George's and Anne Arundel counties. The warning says we can expect the high winds to reach their strongest speeds between 10 a.m. and 5 a.m. Saturday.


And that returns us to the issue of wildfire dangers.

UPDATE, 4 p.m.: The NWS has issued a Red Flag Warning for the entire state of Maryland east of Cumberland. The warning is in effect from 9 a.m. until 9 p.m. Saturday. Expect sustained winds from 25 to 35 mph, with gusts betweeen 50 and 60 mph.  


Relative humidities will be desert-like, between 15 and 25 percent. High winds and dry fuels only add to the danger that discarded cigarettes or careless outdoor burning will ignite a fire that will quickly get out of control.

Temperatures will cool slowly behind the front, holding in the upper 40s to near 50 degrees through the weekend, even under sunny skies. Forecast models show another storm system approaching for President's Day. Forecasters are looking for a 40 percent chance of rain Monday. And with temperatures falling back into the 20s Monday night, some of the models are raising the possibility of the rain mixing with or changing to snow overnight into Tuesday.

"Confidence is low" on that snow thing, forecasters say. So let's not think about that. 

(SUN PHOTO: Jed Kirschbaum, 2003)

Posted by Frank Roylance at 10:41 AM | | Comments (1)
Categories: Forecasts

February 16, 2011

Enhanced fire danger as weather warms

Low humidities and gusty winds continue to raise the risk of wildfires this week.

The National Weather Service has issued a Special Weather Statement this morning reminding Marylanders from Baltimore south that "Open burning of any type is considered very hazardous this Brush fire Marylandtime of year. Accidental escaped debris burns are the number one cause of wildfires."

Forecasters predict relative humidities between 25 and 30 percent this afternoon across much of the region The forecast also calls for south winds at 10 to 15 mph and gusts to 25.

The good news is that skies will continue to be sunny, with temperatures Wednesday rising into the mid-50s at BWI-Marshall Airport. We'll have starry skies again tonight, and can look forward to even milder weather on Thursday and Friday. Temperatures Thursday at BWI are forecast to reach  60 degrees, rising to the upper 60s by Friday. Some locations may even break through to the 70s. That's better than 25 degrees above the long-term averages for this time of year.

They're still calling for a cool-down after a cold front pushes through late on Friday. Daytime highs through the long holiday weekend will stick in the upper 40s to near 50 degrees. There is also a 30 percent chance for some rain on Monday afternoon. After four-and-a-half months of below-average precipitation, we can use it.

(AP PHOTO: Cumberland Times-News, Mark Harris, 2001)

Posted by Frank Roylance at 10:35 AM | | Comments (0)
Categories: Forecasts

February 15, 2011

Sunny, dry and warmer ahead, but winter's not done

My wife (unlike myself) apparently got outside into the balmy, 67-degree weather yesterday. Her question for me this morning was, "So, are we done with the snow?"

We'd like to think so. The cold front that swept the warm air away yesterday afternoon has sunk temperatures in Baltimore back into the more nearly normal 30s and 40s. But, as this high 2003 snowstorm Baltimorepressure moves east in the next couple of days we will see winds swing to the south and southwest again, and the thermometer will stretch back into the 60s.

Forecasters at Sterling say BWI-Marshall should top out at 67 degrees or so on Friday (map below).

But, here in the middle of February, we can't count winter down for the count. Not yet. On Friday night forecasters are calling for another cold front to pass through. Saturday's high will drop back into the 50s; Sunday will only make it to the 40s, and Monday looks like it won't escape the 30s. We could also see some cold rain.

Nope. Sorry. It's still winter, and while the sun is stronger and warming air from the south is reaching us from time to time now, we're not in the clear yet.

Today is the eighth anniversary of the start of the Feb. 15-17 "President's Day Weekend Storm" that dropped 26.8 inches at BWI in 2003 (photo, left). That's still the top-ranking three-day storm for Baltimore, and the top storm overall.

March and April snowstorms are also well-within our weather parameters. The March 28-29 "Palm Sunday Storm in 1942 still ranks sixth overall for Baltimore at 22 inches, and the 5th-deepest two-day storm. And the 9.4-inch April Fools Day Storm" in 1924 is still on the books as the deepest April storm's forecasters think the persistent cold we've experienced for much of the winter is done. But we can still expect some "cold shots" ahead:

"The main point's long range forecasters want people to take away from the long-range forecast is that more cold shots and wintry events will occasionally hit areas generally north of Interstate 70 or 80 from the Plains into the East in the coming weeks.

"However, the general thinking is that the persistent colder-than-normal conditions that have gripped these areas December through early February is over. Temperatures are expected to make bigger fluctuations from here on out, alternating cold with warmth."

My shovel is still on the porch.

And here's another prediction I heard from a forecaster: After a La Nina winter like this one, we should expect more violent spring weather - tornadoes - as cold air to the north and warm air to the south begin to clash. You heard it here first. 

(SUN PHOTO: Karl Merton Ferron, Feb. 16, 2003)

Posted by Frank Roylance at 11:10 AM | | Comments (2)
Categories: Forecasts

February 14, 2011

Monday will be windy, sunny, 64

Is it too late to take a mental health day? Forecasters out at Sterling are calling for a sunny day today with a high that could reach 64 degrees at BWI-Marshall Airport. If so, it would be the first day to reach 60 degrees since, well, Jan. 2 (when the high was 60).

The real news for those of us obsessed by weather stats is that this morning's low of 48 degrees at BWI was the warmest overnight low since Oct. 28, when the mercury slipped no lower than 51. That probably won't be the low for the date, however. There's a cold front due to pass through today, and this evening's temperatures will likely fall below 48 before midnight, on their way to a forecast low of 29.

Tuesday will feel colder, more like the average for this time of year, with a forecast high of just 46 degrees. But as the high pressure system behind the front builds in, things will start to warm up NOAA/NWSagain quite nicely.

As the high moves east, we'll fall under the return flow, with warm southerly breezes by Wednesday. That will push daytime highs back into the 60s for Thursday and Friday before the next cold front sweeps through Friday night and throws us all back into harsh reality. It's still February, and we're looking at highs by Sunday back in the 40s. 

More immediately, forecasters say we are looking at some high winds this afternoon and tonight behind the cold front.

The National Weather Service has issued Wind Advisories (brown on map) for all of Maryland except the Lower Eastern Shore until 10 p.m. Monday. Winds later today will rise to between 20 and 30 mph, with gusts to 45 or 50 mph. In addition to the high winds, the forecast calls for relative humidities Monday afternoon of 20 to 30 percent. From NWS:

"A Wind Advisory means that wind gusts in excess of 45 mph are expected. Winds this strong can make driving difficult, especially for high-profile vehicles. Use extra caution."

From Howard, Montgomery and Anne Arundel counties south, including the central Shore counties, there is also a Red Flag Warning (red on map) in effect until 6 p.m.

"A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. A combination of strong winds, low relative humidity and warm temperatures will create explosive fire growth potential."

Crush those smokes!

Posted by Frank Roylance at 10:18 AM | | Comments (1)
Categories: Forecasts

February 13, 2011

A sunny week ahead, temps climbing to 65

And you thought this week would never come...

Brush fire MarylandAnd yet, here we are, with the forecasters putting the persistent cold and threat of the dreaded "wintry mix" behind them. There is a warm front passing through the region today (Sunday) and skies will begin to clear up. High temperatures are expected to reach into the low 50s Sunday and the upper 50s Monday.

Our winds will pick up on Monday as a cold front tied to a low passing well to our north  goes by. Winds will gust to 35 or 40 mph.

That, low humidities and the relative lack of precipitation and diminishing snow cover will add up to an enhanced danger of wildfires Monday. Forecasters say they may need to issue a Fire Weather Watch later Sunday, most likely in Southern Maryland where moisture levels are lowest.

So crush those smokes and be careful with outdoor burning.

With high pressure dominating all week, by mid-week we will fall under the mild, return flow. Sunshine will prevail, with highs creeping into the 60s Thursday and Friday. That's about 20 degrees above the average for this time of year. A cold front due by the weekend may turn things around again, with more seasonable weather.

(SUN PHOTO: David Hobby, 2004)

Posted by Frank Roylance at 9:47 AM | | Comments (0)
Categories: Forecasts

February 10, 2011

Sunny skies ahead, but bundle up tonight

You could actually feel the warmth of the sun on your face this morning. Even though temperatures are stuck below freezing, and there is bitter cold weather due tonight, the sun is getting noticeably stronger as we get to the middle of February. And there are warmer days just ahead.

The snow overnight didn't get much farther north than Baltimore. BWI-Marshall reported light snow between 8 p.m. and midnight, but it amounted to no more than a "trace. There was a trace reported in Pimlico, too, and in Fallston. The most anyone measured in the region was an inch, reported in Waldorf and St. Charles, down in Charles County.  OC Boardwalk web cam

The Eastern Shore received a little snow, too. The Boardwalk web cam shows a dusting that is quickly melting away as the sun hits it. Bishopville, in Worcester County reported 1.3 inches to the CoCoRaHS Network, while Salisbury, in Wicomico, reported 1.2 inches. Princess Anne, in Somerset, had an inch, too.

Forecasters out at Sterling are calling for clear skies and a low tonight of 18 degrees at BWI. (It should be a bit milder downtown and near the bay.)

That should be the low point going forward, as temperatures are expected to moderate into next week. Highs should reach the 50s by Sunday, and stick there for a while. Lows will rise out of the teens and reach the 30s by Sunday night. That's warmer than today's high. 

And there's no mention of precipitation anywhere in the 7-day forecast.

Posted by Frank Roylance at 12:00 PM | | Comments (1)
Categories: Forecasts