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 | Permalink | Comments (0)
Categories: Forecasts
        

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 baltimoresun.com at 7:31 AM | Permalink | Comments (1)
Categories: Forecasts
        

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 baltimoresun.com at 7:27 AM | Permalink | Comments (0)
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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 baltimoresun.com at 7:38 AM | Permalink | Comments (0)
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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 baltimoresun.com at 7:03 AM | Permalink | Comments (0)
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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 baltimoresun.com at 7:05 AM | Permalink | Comments (1)
Categories: Forecasts
        

We're in for a drippy day today in Central Maryland as we wait for the next cold front to move 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."

Friday 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, AccuWeather.com 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 | Permalink | Comments (2)
Categories: Forecasts
        

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 cold 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 AccuWeather.com 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 admit 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 AccuWeather.com 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 day 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.

Shower 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.

AccuWeather.com 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 AccuWeather.com 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: 

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 | Permalink | Comments (1)
Categories: Forecasts, Winter weather
        

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-inch 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 before 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.

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 | Permalink | Comments (0)
Categories: Forecasts
        

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 front 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 AccuWeather.com'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 | Permalink | Comments (0)
Categories: Forecasts
        

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 temperatures 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 | Permalink | Comments (1)
Categories: Forecasts
        

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

Well, 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 | Permalink | Comments (3)
Categories: Forecasts
        

... 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 Airport, 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 AccuWeather.com

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 | Permalink | Comments (4)
Categories: Forecasts
        

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.

First, 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 AccuWeather.com'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 | Permalink | Comments (2)
Categories: Forecasts
        

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, blah, 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 | Permalink | Comments (2)
Categories: Forecasts
        

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, rising 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 | Permalink | Comments (1)
Categories: Forecasts
        

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 enough 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 AccuWeather.com'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 | Permalink | Comments (5)
Categories: Flooding, Forecasts
        

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 an 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.

The 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 | Permalink | Comments (3)
Categories: Forecasts
        

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 ahead 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." 

AccuWeather.com 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 | Permalink | Comments (1)
Categories: Forecasts
        

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 | Permalink | Comments (0)
Categories: Forecasts
        

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

Forecasters 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 | Permalink | Comments (1)
Categories: Forecasts
        

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 thunderstorms. 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 truly 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 | Permalink | Comments (4)
Categories: Forecasts
        

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 we 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 is 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 | Permalink | Comments (0)
Categories: Forecasts
        

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:

"THE WARM MOIST TROPICAL AIR MAY OVERRIDE COOLER AIR IN PLACE
CAUSING A PROLONGED PERIOD OF PRECIPITATION DURING THIS TIME.
HOWEVER...THERE IS STILL A GOOD DEAL OF UNCERTAINTY IN THE EXACT
TRACK OF TROPICAL STORM LEE. WILL CONTINUE TO MONITOR OVER THE
NEXT SEVERAL DAYS."

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

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 Mexico, 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

The 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 | Permalink | Comments (1)
Categories: Forecasts
        

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. 

The 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

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:

"MINOR TO MODERATE DAMAGE IS LIKELY TO MANY MOBILE HOMES...
ESPECIALLY THOSE THAT HAVE CANOPIES...AWNINGS...OR CARPORTS.
POORLY CONSTRUCTED HOMES MAY SUSTAIN MINOR WALL DAMAGE AND PARTIAL
ROOF REMOVAL. OTHER HOMES MAY HAVE MINOR ROOF AND SIDING DAMAGE.
SOME LOOSE OUTDOOR ITEMS WILL BE TOSSED AROUND AND MAY CAUSE
ADDITIONAL DAMAGE. A FEW POWER LINES WILL BE KNOCKED DOWN
RESULTING IN SCATTERED POWER OUTAGES. SOME LARGE BRANCHES OF
HEALTHY TREES WILL BE SNAPPED. MOST NEWLY PLANTED TREES AND SHRUBS
WILL BE DAMAGED OR UPROOTED."

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 | Permalink | Comments (8)
Categories: Forecasts, Hurricanes
        

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 would 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:

"AT THIS POINT THE LATEST CONSENSUS TRACK WOULD SUGGEST A PERIOD OF
STRONG POTENTIALLY DAMAGING WIND AND HEAVY POTENTIALLY FLOODING
RAIN (MAINLY NEAR AND ALONG THE COAST) FROM FRIDAY NIGHT
(PRECEDING BANDS OF SHOWERS) THROUGH SATURDAY INTO SATURDAY NIGHT
BEFORE LIFTING TO THE NE SUNDAY."

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 | Permalink | Comments (12)
Categories: Forecasts, Hurricanes
        

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.

They'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.

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 AccuWeather.com's take on the storm.

AccuWeather.com 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 | Permalink | Comments (8)
Categories: Forecasts, Hurricanes
        

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.

The 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..."

AccuWeather.com 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 | Permalink | Comments (4)
Categories: Forecasts
        

The first hurricane of the 2011 Atlantic season was leaving Puerto Rico and moving toward the northern 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. AccuWeather.com 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.

Hurricane 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.

The 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:

"IT WOULD NOT SURPRISE ME IF THIS CYCLONE BECAME A MAJOR HURRICANE AT
SOME TIME DURING ITS LIFETIME"

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."

AccuWeather.com'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 | Permalink | Comments (1)
Categories: Forecasts, Hurricanes
        

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 disturbances 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

The 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

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 | Permalink | Comments (0)
Categories: Forecasts
        

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:

24 HOURS ENDING MONDAY MORNING:

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

24 HOURS ENDING SUNDAY MORNING:

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 | Permalink | Comments (2)
Categories: Flooding, Forecasts
        

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.

Low 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 | Permalink | Comments (1)
Categories: Forecasts
        

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 evening 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 | Permalink | Comments (3)
Categories: Forecasts
        

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.

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 inches

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 | Permalink | Comments (0)
Categories: Forecasts
        

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 weekend 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

"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 | Permalink | Comments (1)
Categories: Forecasts
        

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." 

There 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

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 | Permalink | Comments (5)
Categories: Forecasts, Heat waves
        

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 weather 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 | Permalink | Comments (0)
Categories: Forecasts, Heat waves
        

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 idea, 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 | Permalink | Comments (6)
Categories: Forecasts
        

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 | Permalink | Comments (1)
Categories: Drought, Forecasts
        

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 Tuesday'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.

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 | Permalink | Comments (0)
Categories: Forecasts
        

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 downtown 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 and 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 60s), 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

I 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 | Permalink | Comments (2)
Categories: By the numbers, Forecasts
        

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. 

For 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 | Permalink | Comments (2)
Categories: Forecasts
        

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: 

"AN EXCESSIVE HEAT WATCH MEANS THAT A PROLONGED PERIOD OF HOT
TEMPERATURES IS EXPECTED. THE COMBINATION OF HOT TEMPERATURES AND
HIGH HUMIDITY WILL COMBINE TO CREATE A DANGEROUS SITUATION IN
WHICH HEAT ILLNESSES ARE POSSIBLE. DRINK PLENTY OF FLUIDS...STAY
IN AN AIR-CONDITIONED ROOM...STAY OUT OF THE SUN...AND CHECK UP
ON RELATIVES AND NEIGHBORS."

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 fire 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." 

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 | Permalink | Comments (1)
Categories: Forecasts
        

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 the 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.

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 | Permalink | Comments (5)
Categories: Forecasts, Heat waves
        

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.

You'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 | Permalink | Comments (0)
Categories: Forecasts
        

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 | Permalink | Comments (0)
Categories: Forecasts
        

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 blogger 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 Baltimore 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 | Permalink | Comments (0)
Categories: Forecasts
        

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.

"A HEAT ADVISORY MEANS THAT A PERIOD OF HOT TEMPERATURES
IS EXPECTED. THE COMBINATION OF HOT TEMPERATURES AND HIGH
HUMIDITY WILL COMBINE TO CREATE A SITUATION IN WHICH HEAT
ILLNESSES ARE POSSIBLE. DRINK PLENTY OF FLUIDS...STAY IN AN
AIR-CONDITIONED ROOM...STAY OUT OF THE SUN...AND CHECK IN
ON RELATIVES AND NEIGHBORS.

"TAKE EXTRA PRECAUTIONS IF YOU WORK OR SPEND TIME OUTSIDE.
WHEN POSSIBLE...RESCHEDULE STRENUOUS ACTIVITIES TO EARLY
MORNING OR EVENING. KNOW THE SIGNS AND SYMPTOMS OF HEAT
EXHAUSTION AND HEAT STROKE. WEAR LIGHT WEIGHT AND LOOSE
FITTING CLOTHING WHEN POSSIBLE AND DRINK PLENTY OF WATER.

"TO REDUCE RISK DURING OUTDOOR WORK...THE OCCUPATIONAL SAFETY
AND HEALTH ADMINISTRATION RECOMMENDS SCHEDULING FREQUENT
REST BREAKS IN SHADED OR AIR CONDITIONED ENVIRONMENTS.
ANYONE OVERCOME BY HEAT SHOULD BE MOVED TO A COOL AND
SHADED LOCATION. HEAT STROKE IS AN EMERGENCY - CALL 9 1 1."

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

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 residents 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.

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: www.baltimorehealth.org/coderedinfo 

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 | Permalink | Comments (4)
Categories: Forecasts
        

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 | Permalink | Comments (5)
Categories: Flooding, Forecasts
        

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 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 | Permalink | Comments (0)
Categories: Forecasts
        

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 another 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 | Permalink | Comments (1)
Categories: Forecasts
        

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 the 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 | Permalink | Comments (1)
Categories: Forecasts
        

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 predicting 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 | Permalink | Comments (4)
Categories: Forecasts