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July 31, 2007

TS Chantal is no threat

Please don't tell my editors I've posted this. I'm on vacation and if they figure it out, they'll take me for an obsessive compulsive and expect me to monitor the Blog and post from my beach chair.  Okay? Thanks.

Now. As for Chantal... Yes, I lost my bet. We have had our third named storm of the 2007 Atlantic hurricane season, and the first since June 2. But no, it is not a threat to anyone except shipping, and fish. And maybe Iceland by the weekend.

Chantal is a freak. Currently blowing with maximum sustained winds of 50 mph, it formed Monday in the open Atlantic between Bermuda and Cape Cod. It's headed away from the U.S. coast and will very quickly become "extra-tropical" - meaning it will be absorbed into North Atlantic frontal systems and cease to be "tropical" in its mechanics. 

That said, here is the forecast storm track. Here is a satellite view. That's Chantal up there south of Nova Scotia. And here is the advisory.

Tropical storms are supposed to be forming in the much warmer waters of the eastern Altantic, or the Caribbean or even the Gulf of Mexico. Some even form in the western Atlantic, off the Bahamas, or Florida, where the surface water temperatures are 80 degrees or more. So wake me when a real storm pops up out there. Thanks. Where are my shades?

Posted by Frank Roylance at 8:21 PM | | Comments (1)
Categories: Hurricanes

July 26, 2007

Gone fishin'

Your WeatherBlogger will be taking a few days off to enjoy the weather, pour water on dead grass and visit the in-laws. We're betting we'll be back on duty before the drought ends, and before the first big storm makes it out of the tropics. In the meantime, talk amongst yourselves.
Posted by Frank Roylance at 4:52 PM | | Comments (2)
Categories: Notes to readers

New NOAA data bouy deployed

Looking for information about winds, waves and water conditions out on the bay? The National Oceanic and Atmospheric Administration has just deployed a third data bouy in the Chesapeake, this one at the mouth of the Patapsco River.

All the information its sensors gather on winds, air temperature, water temperature, salinity, waves and much more is sent by wireless telemetry to the Internet. You can dial it up anytime by visiting this page. Here is the main page.

Explore. There is an impressive amount of data from the Patapsco bouy, as well as others at the mouth of the Potomac and at Jamestown, Va. You can construct graphs showing the changing conditions over time. The times are in Universal Time (UTC). That's currently four hours ahead of EDT.


Posted by Frank Roylance at 3:10 PM | | Comments (0)
Categories: Cool sites

New data show Md. drought deepening

Maryland's drought is deepening as more territory is added the region experiencing "severe" drought conditions, according to new data released this morning by the U.S. Department of Agriculture.

The USDA's latest Drought Monitor map shows more than 75 percent of the state is officially in drought. That's unchanged from last week. The ratings are based on measurements of rainfall, soil moisture, streamflow and the health of vegetation as measured by satellites.

But the new drought map has expanded that portion of the drought-affected area now under "severe" drought. It now includes parts of southern Washington County, southwestern Frederick County and western Montgomery County. Southern Maryland, too, including Charles, St. Mary's and southern Calvert counties, remain under severe drought conditions. In all, 17 percent of the state is experiencing severe drought conditions, up from 9 percent last week.

"Moderate" drought continues in a swath from eastern Allegany County to the lower Eastern Shore, including Baltimore City and southern Baltimore County.

The remaining 25 percent of the state, including far western Maryland and the northeast corner (including northern Carroll, Baltimore and Kent countiues, and all of Harford and Cecil), remains "abnormally dry" on the USDA map.

Several Maryland communities, including Frederick, Mt. Airy and Westminster, have already announced voluntary or mandatory watering restrictions. State agriculture officials have submitted data on crop losses to Gov. Martin O'Malley, who was expected to announce today that he will seek a federal drought disaster declaration for portions of the state worst-hit by the dry weather.

Rainfall at Baltimore-Washington International Airport has been unusually scant since mid-April. Since May 1, the airport has recorded a precipitaion shortfall of about 6 inches. The actual deficit in many locations may be far worse, since the airport experienced a very localized 1.8-inch thunderstorm July 10. Spotty showers across the region this week have done little to ease the dry conditions.

Although there are chances for showers and thunderstorms each day for the next week, the National Weather Service forecast shows no prospects for sustained and restorative rains. The tropics, which have frequently provided drought relief for Maryland in the form of remnant tropical storms, remain quiet. 

Some farmers on the lower Eastern Shore and in Southern Maryland say they have had no significant rain in several months. Corn, soybean and hay losses are said to be as high as 50 to 60 percent in some regions.

So far, groundwater resources and the urban reservoir system in Central Maryland are said to be holding up well. But public works officials say supplies could become stretched if the dry weather continues well into August.

Here's the national Drought Monitor map, showing how our conditions fit in with those across the lower 48 states.

Posted by Frank Roylance at 10:41 AM | | Comments (0)
Categories: Drought

July 25, 2007

"Feeling the Heat" in Baltimore

There is virtually no scientific debate anymore about whether temperatures are rising around the globe, and little more about whether human activity is playing a significant part in that global warming. The larger debate now is over how much should or can be done to reduce mankind's contributions to a worrisome process that is well underway.

Environment Maryland, a statewide environmental advocacy group, this week released a report on rising temperatures in the United States at the start of the 21st century, and issued a call for action on a list of remedies that could be advanced in the halls of local, state and national legislatures, and at home.

Among the findings in the group's report - "Feeling the Heat: Global Warming and Rising Temperatures in the United States" - is that 2006 was the second-warmest year on record for the lower 48 states. Some 87 percent of the weather stations studied saw average temperatures in 2006 that were at least a half-degree above the 30-year norm.

The average temperature at BWI during 2006 was 2.9 degrees above the 30-year average recorded between 1971 and 2000.

Well, one warm year does not constitute a trend. The report also notes that the years 2000-2006 at BWI also averaged more than the 30-year norm, by 1.4 degrees. That's not conclusive of anything either. But the science behind the reality of global warming is very compelling, so we won't quibble. Environment Maryland is merely trying to make a point, and to make that point relevant to its constituency - the people of Maryland.

Global warming is real, they're arguing, and it will have far-reaching consequences for our society, for our health and our economy, and for the environment of which we are a part. And, there are things we can and should do to reduce our destructive influence on the planet that gave us life and still must sustain us.

Most of it we have heard or read before. But it is well worth a refresher. You can read the report's Executive Summary here. And there is a link on that page to the full report via pdf file.

Posted by Frank Roylance at 1:24 PM | | Comments (0)
Categories: Climate change

Mars weather threatens rovers

Okay, so it's a long way from Maryland. But the weather on Mars is pretty interesting, and we sometimes have better imagery to look at. In this case, it's raging dust storm, and it threatens to Mars dust storm - NASA photoobscure the sunlight long enough to rob NASA's twin rovers, Spirit and Opportunity, of their solar electric power.

That elecricity is vital to keeping the rovers' batteries charged and their innards warm and functioning. Deprived of sunlight long enough, and the two robots, now in the middle of their fourth year on the Martian surface, will die. Read more about it here.

Here are a pair of images from a Mars orbiter showing how the global dust storm has obscured the surface. 

And here is a satellite shot of a dust storm on Earth, over Pakistan and Afghanistan..

Posted by Frank Roylance at 10:18 AM | | Comments (0)
Categories: Cool pictures

July 24, 2007

Blanket morning

Just back from a Jacksonville, Fla. wedding, where the heat, the humidity and the mosquitoes make one wonder why anyone lives down there in the summer. Arrived at BWI last night to find the temperature 20 degrees cooler thanks to this nice Canadian air mass. Opened the house up before we hit the sack, and woke up reaching for the blankets.

It was 56 degrees on the WeatherDeck in Cockeysville this morning. The instruments here at The Sun fell to 68 degrees by 6 a.m. The official low, at BWI-Marshall, was 58 degrees, in the pre-dawn hours. That was just 3 degrees shy of the record low for the date for Baltimore - 55 degrees, set on this date in 1985.

In fairness to the Floridians, the same cool air that has made life so pleasant here for the last couple of days, did finally make it all the way to north Florida yesterday. The sky cleared and, except for the remarkably strong sun at that latitude, it was much more tolerable - in the 80s, and much drier. A bit of shade and something tall and cool made it just about perfect.

The rest of the week for us looks unusually mild for this time of year, with highs only in the mid-80s and comfortable humidity. The normal high for this time of year at BWI is 88 degrees. The chance for a thundershower or two increase as the week wears on. Here's the official forecast.

We can sure use the rain.  


Posted by Frank Roylance at 10:06 AM | | Comments (1)
Categories: By the numbers

July 20, 2007

Maryland drought deepens

The drought that has plagued the southeastern United States this spring and summer has been spreading northward gradually into Maryland. Last week, 37 percent of the state was in what the U.S. Department of Agriculture considers "moderate" drought. With the issue of the new Drought Monitor map yesterday, the percentage of the state in moderate to "severe" drought has expanded to almost 85 percent.

(7/26 NOTE: That 85 percent figure is incorrect. The actual number is 75 percent. We misinterpreted a data table from the USDA and, somehow, nobody called us on it. The error was discovered this morning. We're fixing it now in Thursday's Web story.  Your WeatherBlogger regrets the error.)

(Drought conditions are determined by a complex formula that takes into account measurements of soil moisture, streamflow, precipitation and the health of vegetation as measured by satellite imagery.)

 Here's the national map. It shows almost the entire nation east of the Mississippi enduring  unusually dry weather, as are the far Western states. Only the nation's midsection is enjoying more or less normal rainfall and soil conditions. 

The state's worst conditions have settled over Southern Maryland, including Charles, St. Mary's and southern Calvert counties, all now in a severe drought. Here's the state map.

Moderate drought conditions prevail from eastern Allegany County, across much of central Maryland, including Baltimore and southern Baltimore County, to the lower Eastern Shore. The rest of the state - including far western Maryland and the northeast corner (from northern Carrol, across northern Baltimore, Harford and Cecil counties) - is rated "abnormally dry."

It is the most widespread drought in Maryland since October 2005, when the entire state was in moderate drought.


Posted by Frank Roylance at 8:44 AM | | Comments (1)
Categories: Drought

July 19, 2007

Is dust over Atlantic stifling hurricanes?

The 2007 Atlantic hurricane season continues to be very tranquil. After an early start that spawned two quick storms in late May and early June, the tropics have settled down quite nicely. (Of course, as soon as I note such trends, they reverse. Beware.) Here's all the National Hurricane Center is watching at the moment.

Saharan dust over E. Atlantic - NASA Terra satelliteOne explanation for the failure of the eastern Atlantic to generate tropical storms at this time of year has been the presence of large clouds of Saharan dust in the atmosphere. Some scientists believe such clouds stifle the formation of the kinds of tropical storms that can eventually reach the Caribbean and the U.S. coast. Here's another shot.

Satellite imagery in recent weeks has been documenting exactly such clouds off West Africa. At left is a shot of the eastern Atlantic, taken Monday by NASA's Terra Earth-observing satellite. Some African dust has been tracked as far west as the Caribbean.

Officially, this has been forecast to be an abnormally active hurricane season - not as busy as the record season of 2005, but busier than last year's unexpectedly quiet summer. Here is the latest National Weather Service estimate for the current season.

Posted by Frank Roylance at 12:49 PM | | Comments (0)
Categories: Hurricane background

July 18, 2007

PM rain welcome; great weekend ahead

We're going to have to contend with some heat, humidity and a threat of thunderstorms for the next two days as we wait for a Canadian "cool" front to push its way down and dry the place out. It's already headed toward the 90s this morning in downtown Baltimore.

But once the front clears the region on Friday, we'll enjoy a terrific weekend, with some clear, dry air and daytime highs in the low 80s - about 5 degrees below the long-term averages for Baltimore at this time of year. Here's the official forecast.

Headed for the ocean? Here's the beach forecast.

We can only hope that whatever rain we get today through Friday will be as widespread as possible, and with as little storm damage as we can get away with. We are still rated "abnormally dry" in the Baltimore-Washington metro region. Here's the latest drought map, now almost a week old. Southern Maryland and the lower Shore are in moderate drought.

Rainfall numbers at BWI are not a good guide for the rain shortage in the region. A heavy downpour there last week dropped almost 2 inches of rain on the airport instruments, and the official stats belie just how dry most of the region has been. Even here at The Sun, our rain gauge has collected barely three-quarters of an inch of rain in July. The airport has seen nearly 3 inches.

Readers?  Anybody got a rain gauge? I'd love to see your reports on July rainfall in your location.


Posted by Frank Roylance at 11:02 AM | | Comments (0)
Categories: Forecasts

Southern Maryland, Lower Shore now in drought

Must have been busy last week, because the new Drought Monitor map slipped by me. Just noticed that it placed all of Southern Maryland and the Lower Eastern Shore under "moderate drought" conditions for the first time this summer.

The rest of the state, except for a slice of Cecil County, remains "abnormally dry."

Here's the Maryland map. Here's a broader view. showing most of the nation east of the Mississippi to be dry to exceptionally dry. The western states are also very dry, of course, leaving only the Plains, or most of that region, enjoying normal rainfall and soil moisture conditions.

Posted by Frank Roylance at 8:44 AM | | Comments (0)
Categories: Drought

July 17, 2007

Harford tornado rated an EF-1

The National Weather Service has rated Monday evening's Harford County tornado an EF-1 on the "Enhanced Fujita Scale."  That suggests maximum winds between 86 and 110 mph.

Sun photo by Kim HairstonHere's the statement this afternoon from the Sterling forecast office:




For a detailed list of damage reports from Monday's storms, click here.

The June 13 tornado that ripped up woodlands north of Butler, in Baltimore County, was rated an EF-0, with top winds between 65 and 85 mph, the lowest rating on the scale.

Posted by Frank Roylance at 4:10 PM | | Comments (0)
Categories: Tornadoes

Harford blow was tornado

An inspection team from the National Weather Service is on its way back to Sterling, Va. this morning after inspecting damage from last evening's storm in Harford County. The preliminary word from their three-hour tour of the Fallston area is that the damage was caused by a small twister.

"The damage we saw suggests that, yes, it was a tornado," said David R. Manning, warning coordination meteorologist for the National Weather Service's Baltimore-Washington Forecast office in Sterling.

There was no immediate estimate of the storm's intensity on the Enhanced Fujita Scale. "I didn't see damage that would suggest a strong tornado, but there was some fairly significant damage to trees and a lot of power lines were taken down."

"At this point it looks like it was on the ground for a few miles - less than 10 but more than 3," Manning said. ""We have not mapped out all the locations yet completely."  The twister's path of destruction stretched from near Fallston, southeastward to very close to Abingdon. Its width varied from 100 to 150 yards.

A Fujita rating and a better estimate of the length of the tornado's path of destruction across Harford County is expected later today in a public information statement to be published on the Sterling forecast office Web site

Manning was also part of the team that inspected damage from the F-0 tornado that ripped through woodlands north of Butler in northern Baltimore County on June 13. The Fallston damage suggests yesterday's storm was bigger - "a little wider and a little longer," he said.

The fast-developing thunderstorm boiled up over northern Baltimore County around 5:30 p.m., knocking down trees near Old York Road and Troyer Road in Monkton, and near Corbett Road in Phoenix. 

The weather service issued a severe thunderstorm warning at 5:35 p.m., Manning said, followed by a tornado warning for Harford County at 6:12 p.m.

The storm crossed into Harford County, snapping and toppling large trees in the Fallston area. Many of the trees took power lines and poles down with them. Utility and highway crews were still clearing and repairing the damage this morning.

Here's the story in this morning's Sun

Manning said he saw trees as large as 3 feet in diameter at the trunk that had been felled by the storm. "Some trees were topped, with either parts or most of them snapped off. Most of them were pushed over."

The key to distinguishing tornado damage from straight-line wind damage is the orientation of the downed trees and debris.

"If they diverge, it's straight-line wind," he said. He compared the effect to that of pouring a bucket of water onto the floor. The water moves out and away from the center. In a tornado, the debris is drawn in toward the center of the storm's track.

Fortunately, he said, yesterday's damage was almost entirely to trees and power lines. "A lot of the trees that fell, even though they were near homes, didn't fall on homes," Manning said. "I did see a few locations where limbs or trees did fall on homes, but I didn't see any major structural damage where I looked."

Accompanying Manning on the inspection tour this morning was another meteorologist from the Sterling forecast office, and a representative of Maryland Emergency Management.



Posted by Frank Roylance at 10:21 AM | | Comments (0)
Categories: Tornadoes

July 16, 2007

"A broken record..."

"A chance of showers and thunderstorms ... a high near 92."  That's the forecast for today. And tomorrow. And the next day. Then we get a break ... "A chance of showers and thunderstorms ... a high near 88."

If you don't sense a difference, you can be forgiven.

This week marks the height of summer, statistically the week of highest average daily highs and lows for Baltimore. It's also going to be plenty humid. You've heard of "sweater weather"? Well, this is "sweat weather." Even if you can take the heat, you'll likely want to run the AC to cut the humidity.

Forecasters out at Sterling say the explanation for what they concede is a "broken record" lineup for the week's weather is a weak front stalled over the region from northeast to southwest. It's leaving us with light and variable winds, lots of sunshine to heat us up during the day, and enough humidity to fuel showers and thunderstorms in the afternoons and evenings. Some could be severe.

This is summer on the Chesapeake, the price we pay for our long, pleasant spring and fall, and short winters.

Posted by Frank Roylance at 9:51 AM | | Comments (0)
Categories: Forecasts

July 13, 2007

Sunset on "Manhattanhenge"

Today is a special day in Manhattan. It is one of just two days each year on which the sun sets directly in the center of all the island's east-west street canyons. The other date is on or about May 28.

Some call the event "Manhattanhenge," suggesting the solar alignments of Britain's Stonehenge monuments. But Manhattan is different. It's tilted.

If the borough's street grid had been laid out precisely north and south, and east and west, the dates of the urban canyon sunrises and sunsets would coincide with the Vernal Equinox and the Autumnal Equinox, the dates when the sun rises and sets due east and west.

But, the city's designers pitched the grid 30 degrees east of due north, more closely aligned to the island's central axis. And that produces these two canyon sunsets a year, and two canyon sunrises (Dec. 5 and Jan. 8).

 photo by Neil deGrasse Tyson, American Museum of Natural History

Baltimore's downtown street grid is aligned more precisely along the north-south, east-west map grid. Streetcorner astronomer Herman Heyn made a study of it all a few years back.

He found that the city's original surveyor, Philip Jones, Jr., used his magnetic compass to determine where north was. He got that right, but he did not correct for the difference between magnetic north and true north (the direction of the North Pole).

Because magnetic north at the time was 3.9 degrees west of true north in 1730, when Jones did his work, (magnetic north moves as the molten metal innards of our planet slosh about, and that shifts the magnetic field.), our streets are not perfectly aligned with true north.

In fact, Heyn found, the original north-south streets run between 2.9 degrees and 3.5 degrees west of true north. Still with me?

But 3 degrees is a far cry from 30 degrees, so our "Baltimorehenge" dates are more nearly matched up with the fall and spring equinoxes. (Because the angle of the sunrises and sunsets change so slowly, a day or two before or after these days would probably still yield a good photo opportunity.) Here are Heyn's calculations:

Sunrises: Sept. 18 and March 25

Sunsets: Sept. 29 and March 12

Posted by Frank Roylance at 11:34 AM | | Comments (0)
Categories: Cool pictures

Mostly summery

Not much that's newsworthy in the forecast ahead. About the best we can say is that it will be very summery in these parts for forseeable future, pretty typical for Maryland in July. High pressure will dominate, but it's a weak system, with increasing moisture arriving on southwesterly winds.

That, and strong solar heating, will introduce some chance for convection (showers and thunderstorms) nearly every day from here into next week. The one likely exception seems to be Saturday. So if you have outdoor plans, get them in motion tomorrow.

Forecasters at the National Weather Service forecast office in Sterling, Va. say we should expect highs in the upper 80s or low 90s for the next seven days. The next "cool" front arrives from the Great Lakes Sunday, but they say it will likely get hung up somewhere in our region, leaving us with a continuing risk (or hope) of afternoon and evening showers and storms.

The next chance for a break into milder, drier weather will be sometime late next week. The tropics remain quiet. If you're shoving off for Bermuda or the Caribbean, you should have smooth sailing.  

And if you're headed for the beach this weekend, here's the (slightly cooler) forecast

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

July 12, 2007

64 F today at Resolute

Devon Island

We weren't the only ones enjoying a gorgeous day today. Researchers with the Mars Institute's Houghton-Mars Project up on Devon Island, in the Canadian Arctic, were arriving for a summer of fun science under conditions chosen because they mimic those astronauts will find on Mars.  Except that the high temperature there today was an unexpectedly mild 64 degrees.

Here are the temperatures that NASA's Mars rover Spirit has encountered. Here is the weather report for nearby Resolute.

And here is a link to the Web site for the expedition. You can watch Web cams (the pictures look like those sent back by NASA's Mars rovers, except that the sky is blue, not pink), and follow the researchers' blog. They're even operating a greenhouse up there. Mars explorers will do better if they can raise some of their own food on the long adventure, and a little greenhouse warming would be a good thing on Mars.

Victoria crater, Mars - photo by rover Opportunity

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

Cat. 4 typhoon threatens Okinawa

The Atlantic basin remains quiet as this year's hurricane season advances. But Okinawa and Japan are threatened by a big typhoon that's now spinning in the eastern Pacific. Typhoon Man-yi is sporting top sustained winds of 125 knots (143 mph) with gusts to 150 knots (172 mpg).

That's a solid Category 4 storm. Nothing to be trifled with. And Okinawa is bracing for a big blow. Read more here.

Here's the forecast track, which curls from Okinawa toward the southern islands of Japan over the next few days. Here's how the storm looks from orbit. Quite a nicely formed eye.

Can't get enough of this stuff? Here's the forecast discussion.


Posted by Frank Roylance at 12:18 PM | | Comments (0)
Categories: Hurricanes

July 11, 2007

No nineties today

Our little streak of 90-degree weather has stopped at four days, at least out at the airport. The high at BWI this afternoon stalled at 89 degrees. Downtown was another story. The thermometer at the Maryland Science Center reached 92 degrees, and the high reading here at The Sun was 90 degrees around 4 p.m.

BWI also missed the rain that swept through Washington, D.C. this afternoon. The thunderstorm dropped four-tenths of an inch of rain at Reagan National Airport, and sank the temperature, briefly, from a high of 85 to to 78 degrees. I saw a little, very brief shower outside the newsroom window, but nothing registered on the rain gauge.

The radar loop and the satellite imagery show the cold front we're expecting this evening is still to our north and west. We can expect more showers or storms when that finally rolls through.

So here's the rundown on the 90s so far this year at BWI:

May: 3 days

June: 7 days

July: (through 7/11): 4 days.

Total for 2007 (through 7/11): 14

Total for 2006 (through 7/11): 12

The high readings so far this summer: 97 degrees, on July 9 and June 27.

The high readings by this time 2006: 95 degrees, on May 30 and June 18.

Posted by Frank Roylance at 5:37 PM | | Comments (0)
Categories: By the numbers

More storms, then cooler

Okay, so maybe we WON'T make it back into the 90s today. Forecasters appear to be backing off yesterday's predictions that we would be back in the 90s - or at least an even 90 degrees - this afternoon.

The current forecast out of Sterling puts today's high at BWI at a "cool" 85 degrees. That's actually a couple of degrees below the average for a July 11 in Baltimore. We'll see. It's already 84 degrees here at Calvert & Centre streets. I think we can expect denizens of downtown Baltimore to see the 90s today, even if the airport, out in suburbia, doesn't.

Car crushed by tree in Hampden - Sun photo by Karl Merton FerronThe real weather news for today is that we have a good shot at more thunderstorms this afternoon. Sterling puts the chances at 60 percent. But then they put yesterday's risk of thunderstorms at 20 percent, and look what happened!

Today's storms are the real deal - the harbingers of the long-awaited cold front that will move this hot, humid, polluted air mass out of here at last. The next few days should see high temperatures back in the mid-80s, with lower humidities. A secondary front will cross the region on Saturday, they tell us, raising the chances for a small risk of showers or thunderstorms on Friday.

Then, by Sunday, we may be back in the 90s, with increasing heat and humidity as the new week rolls out. This is still July in Baltimore, after all.



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

July 10, 2007

Surprise storm pummels Baltimore

With no more than a few minutes warning, a large thunderstorm popped up southwest of Baltimore shortly after 1 p.m. this afternoon. Heavy rains and hail the size of pennies and pingpong balls dropped on downtown streets and parking lots as the storm tracked north and east. Here's the radar loop.

The storm dropped temperatures at The Sun by 16 degrees - from 94 degrees to 78 degrees in less than 30 minutes.

The storm arrived just  minutes after the National Weather Service issued a "severe storm warning" for Anne Arundel County at 1:25 p.m. That warning was later extended to include the city and Baltimore County.

Rain fell, briefly, at a rate of more than 7 inches an hour at The Sun. In 15 minutes, more than a third of an inch had passed through the rain gauge.

Readers? Let's hear from you. Leave a comment and describe what you're seeing out there.


Posted by Frank Roylance at 1:52 PM | | Comments (8)
Categories: Events

107.4 degrees, still the record

Seventy-one years ago today, the official thermometer in downtown Baltimore climbed where it had never been before. At 3 p.m. on July 10 of that year, the report brought down from the roof of the U.S. Customs House stated it was 107.4 degrees up there for a brief period. And, at least officially, it's never been hotter in Baltimore since.

It could have been even worse. Cumberland reported a torrid 109 degrees, the hottest spot in the state that day in '36. It was the eighth day of a heat wave that was sweeping the nation. Already 421 people had died nationwide, and millions of acres of crops dried up beyond recovery. Twenty-nine Baltimoreans had been overcome by the heat and hospitalized.

Adding violence to misery, a two-hour thunderstorm struck town just before 8 p.m. that evening, toppling trees and knocking out power and phone service over a wide area, especially in North Baltimore. One city home was struck by lightning and set afire. The good news was that the storm also dropped temperatures by 12 degrees, from 94 to 82. But it quickly began rising again.

The city record high bested the previous record high of 105.4 degrees, set on Aug. 6, 1918.

Before the heat wave was over, more than 700 Americans would be dead, one of them in Baltimore. Residents packed their bags for cooler spots. Here's how The Sun described the exodus on July 12, 1936:

"Spurred by the desire to escape the city heat and humidity, thousands of Baltimoreans left town yesterday for the week-end. The steamers of the Old Bay Line and the Chesapeake Steamship Company, plying between Baltimore and Virginia ports, left the city yesterday afternoon with capacity passenger lists. Ferries between Baltimore and the Eastern Shore, and Annapolis and the Eastern Shore, also carried large crowds of travelers. Railroads and bus lines reported more than seasonal travel and the Wilson Line and Tolchester Company reported excursion business had taken a decided leap."

"Mayor (Howard) Jackson. leaving his office for a vacation with his family, left word that municipal offices could suspend business should heat conditions warrant, and provided the interruption would not interfere with the proper conduct of city business.

"Many offices on downtown skyscrapers closed. Some shops also dismissed their forces, in midafternoon. Golf courses and other sports areas were practically deserted as people sought every available cool spot. Traffic police, in the business area, unable to leave their posts, stood throughout the day under the scorching beams of an unrelenting sun."

"Lawns and gardens of suburban homes began to show the effects of the burning sun. Grass was shriveling and in many instances bushes show signs of drying up. Jones Falls, Gwynns Falls, Herring Run and other streams running through the city's limits were below their normal flow line.

"The breeze, coming from the southwest, northwest and west during the greater part of the day, was hot. Even the bay breeze that arrived shortly after the peak temperature of the day was reached brought little relief. It also was hot.

"On South Broadway, in the business district of Eastern Avenue and in Hamilton efforts were made to fry eggs on pavements, without results."

Sun photo by Chiaki KawajiriThe Evening Sun ran a front-page picture on the 10th of young women, fully clothed, stretched out asleep for the night on the grass in Druid Hill Park. The accompanying story said, "Thousands of Baltimoreans had spent the night in the parks, sleeping on the grass and in their automobiles. Others had sought refuge at swimming pools and bathing beaches. But the greater part of the city's populace had simply sweltered in their homes which, in most cases, were too warm to permit much sleep."

People coped as best they could, according to The Evening Sun: "The proprietor of a store in the 600 block Eutaw street removed his coat and collar when he arrived at his place of business this morning. He sat down at his desk in his shirt sleeves. But even that, he decided, was too much. He got up and took off his shirt."

Finally, here's my favorite piece, from the editorial page of The Evening Sun for July 11, 1936. I quoted a bit of it Sunday on the print Weather Page. Here's the entire entry, by an unnamed editorial writer:

"He comes home and says, 'What's this, what's this?' And she tells him it's an electric fan Cousin Carrie let her have while she was out of the city on vacation, and that it makes all the difference in the world in the living room during a terrific hot spell lioke this one.

Used by permission"He asks if it's going to sit there on the living room table. And she says it is. And he says it looks awful there. He asks what makes that awful buzzing noise that sounds like a saw in a sawmill. She says that is nothing except probably the fan needs a little oiling.

"He says he doesn't think much of that. He says the noise gets on his nerves. He says he doesn't see how he's going to stand it. She says it is very funny that he is nervous about a steady noise like that when he never seems to be bothered by having the radio turned on full tilt while he is reading. She says if she has had to put up with the radio all these years, then she thinks he ought to be able to put up with an electric fan for a few hot evenings.

"He says he supposes he can. He says what he objects to is the principle of the thing. He says for years they have gone through hot spells without an electric fan, and he doesn't see why they should suddenly imagine they can't do without one. He says that is what is wrong with the country today, everybody just wants to have an easy time, and the easier the better. He says there is no more of the old pioneer spirit that made us what we are, and trained us to put up with hardships. He says he hates to think of the children growing up soft, and that is what an electric fan will do for them.

"She says it's a nice thing for him to be talking that way. Hasn't he been boasting to them about his air-conditioned office, and how much more efficient he is and more valuable to his employer? And he says, 'Nonesense. That's quite a different matter!"

Thanks to Sun research librarian Paul McCardell for dredging up the old clips.

Posted by Frank Roylance at 9:43 AM | | Comments (0)
Categories: History

July 9, 2007

Temps hit 100 downtown

Sensors at the Maryland Science Center and at the Sun's weather station at Calvert & Centre streets both reached 100 degrees late this afternoon. It was the first time temperatures in Baltimore have hit triple digits since Aug. 3, 2006.

The airport high was 97 degrees. That's plenty hot, but short of the record 103 degrees for this date, in 1936.

Although it was hot enough to make anyone miserable if forced to be outdoors, the relatively low humidity since Saturday has kept the 90-plus heat wave as bearable as it could be. The dew point this afternoon ranged from the high 50s to the mid-60s. Things don't start to feel really sticky at these temperatures until dew points top 70 degrees. (The dew point is the temperature at which moisture would begin to condense in the atmosphere. The closer the dew point to the ambient air temperature, the more humid it feels.)

That said, it was still danged hot. As I write this, a little after 6 p.m., the mercury at The Sun still reads 99 degrees. Whew! And the air quality was "unhealthy" for sensitive groups.

BGE did not reach its record for electric consumption. The record, set last Aug. 3, was 7,198 megawatts. Spokeswoman Linda Foy said the utility anticipated no problems meeting the demand.  

Posted by Frank Roylance at 5:59 PM | | Comments (0)
Categories: By the numbers

Stay inside 'til Thursday

This, all you newcomers, is summer in Baltimore. We've begun what are, over the long haul most likely to be the hottest few weeks of the year in Charm City, with forecast highs well into the 90s. The humidity's risin' and with it the heat index numbers, which only serve to deepen our misery.

You can track the rising numbers here.

Those of us fortunate enough to have air conditioning in our homes and cars - and the income to turn over to BGE and Big Oil to run it - will survive quite nicely with only a few gasps of the real atmosphere as we dash from door to car, and car to door.

Sun photoThe rest of us will have to rely on fans, or the stray breeze off the bay (try the lawn at Ft. McHenry), the city's cooling centers or the kindness of strangers.

We have a long way to go yet. Heck, this is only the third 90-degree day this month (13th this year). Last year we had 18 of them before the month was out (and 39 for the summer).

Relief, such as one can realistically expect at this time of year, will come late Wednesday, as a the next cold front nears. We can look forward to a chance for late-day thundershowers, which will usher in milder temperatures - in the 80s - on Thursday.  

It was about this time of year in 1980 when my family and I - just arrived from the New England coastal town of New Bedford - began to wonder what we had gotten ourselves in for. Our new house had no air conditioning, and the candles on the dining room table were drooping in the near-100-degree heat. So were the kids.

We were driving a Ford station wagon with black vinyl seats and no AC (didn't need it in Massachusetts). We were scalding ourselves on the seats, couldn't touch the steering wheel, and couldn't breathe the air.

But we survived. Couldn't afford AC yet, so we installed a whole-house fan. That cooled the place off pretty well at night. And if we shut the house up early enough we found we could keep it tolerably cool all day. We were lucky to have tall oaks around us, and they helped shade the place. Here are some other tips for keeping the house cool.

Then we bought a used Corolla with AC. It immediately became our car of choice until autumn arrived with temperatures and humidity fit for mortal humans.

Hang in there, all you newbies. You'll adjust.


Posted by Frank Roylance at 11:02 AM | | Comments (0)
Categories: Forecasts

July 6, 2007

Into the oven

NASA photo 

After a fine, seasonably nifty day today, we're headed back into the 90s for the next week or so. The cold front that brought us this week's showers and thunderstorms is past now, and high pressure is building back into the region, clearing the skies and raising the temperature as some of the strongest sunshine of the year beats down on us.

It's no surprise. The next three weeks or so are the hottest of the year, on average. The forecast calls for gradually rising temperatures this weekend, and on into next week. We may bust into the 90s tomorrow, and climb into the upper 90s by the beginning of the week.

As the heat rises next week, so will the humidity. The center of this high pressure will move off the coast, putting us once again into the return clockwise flow. And that will replace the dry, Canadian air we'll enjoy this weekend with increasingly hot, humid air from the Gulf of Mexico and the Atlantic.

Rain will remain scarce for now. The first chance for drops will come Tuesday, with a weak cold front. More likely we'll stay dry until Thursday, when a stronger front arrives with better chances for showers and thunderstorms. And that will clear the way for another fine weekend next week.


Posted by Frank Roylance at 11:22 AM | | Comments (0)
Categories: Forecasts

NWS seeks help verifying tornado

The storms that swept the region on July 4 produced several unconfirmed reports of funnel clouds or a tornado touching down in the region. The National Weather Services is asking for the public's help in finding storm damage that might indicate a true touchdown. Here's their appeal:





Posted by Frank Roylance at 10:54 AM | | Comments (0)
Categories: Notes to readers

July 5, 2007

Twisters menace 4th; more storms today

A report of a tornado touchdown in East Columbia, and a funnel cloud hear Centreville yesterday, prompted authorities to clear the National Mall yesterday afternoon. But there has been no confirmation that any twisters actually touched the ground. Here is a rundown on are storm and damage reports yesterday afternoon, including the reported funnel clouds, lots of hail, some tree and cable damage.

The National Weather Service forecast office in Sterling, Va. has not yet decided whether the reports warrant sending a team out to inspect any damage and verify whether a tornado touched down.

Sun photo - Mauricio RubioThe thunderstorms that swept the Baltimore region last evening dropped widely variable amounts of water. The downpour was torrential, but brief in downtown Baltimore, and the fireworks went off despite a lingering drizzle. Other stations recorded little or no precipitation. Here's The Sun's story on the festivities and the storms.

And here are some rain totals, through midnight, from around the region:

BWI: 0.58 inches

Science Center, Baltimore: 0.86 inches

The Sun: 0.14 inches

Washington National: 0.03 inches

Dulles Int'l: 0.74 inches

Hagerstown: Trace

Martinsburg, W. Va.: 0.02 inches

Recent rains, especially in western Maryland, appear to have eased the dry conditions that have been worsening in recent weeks. The western counties have dropped out of the "moderate drought" category on this week's Drought Monitor maps, although 97 percent of the state is now considered "abnormally dry" - up a tad from last week. The maps reflect conditions on Tuesday of each week, so last night's rain has not yet been taken into account.

There may be more storms, and just plain rain in store for us this afternoon and evening as a cold front approaches and shoves off the coast. Here is the forecast. The threat will vanish by the weekend, and strong sunshine will boost temperatures into the 90s well into next week.

Headed for the beach? Here's the forecast.



Posted by Frank Roylance at 10:43 AM | | Comments (0)
Categories: Events

July 3, 2007

Turning up the heat

You knew this couldn't last. It's July in Baltimore, after all. It's supposed to be really hot, and really humid. Instead, we've enjoyed these beautifully clear, dry, sunny afternoons, and cool, shut-off-the-AC-and-open-the-windows nights. It's been like summer in New Hampshire.

"Amazing weather. If you'd dropped me from outer space, I'd say we'd just celebrated Labor Day, not the day B4 the 4th," said one NWS forecaster in today's forecast discussion from Sterling.

Well, the high-pressure that's brought us this fine weather is moving off the coast and will soon be pumping in more warm, humid air from the Gulf and the Atlantic. It's a familiar scenario. Temperatures climbing, humidity rising, and increasing chances for afternoon showers and thunderstorms.

Here's the forecast. The Fourth should be fine. Highs in the mid-80s with only a 30 percent chance of rain, especially along the PA border. But by Thursday the storm chances reach 50 percent as a new cool front drops across the region. But there won't be any real cooling. With sunnier skies, by Friday we should be seeing highs approaching 90 degrees again. Sunday and Monday should top 90.

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

"We're going in!" - NASA

NASA photo

In the risk-taking spirit of its human pioneer forebears, the Mars rover Opportunity is about to plunge into a crater from which it may never return.

NASA's Mars rover program has been so phenomenally successful over the past 3 1/2 years, with both rovers surviving years beyond their original mission profiles, that the space agency has decided to risk half the fleet by sending one of the robot explorers into a steep crater.

Opportunity is preparing to crawl over the lip of Victoria crater, a deep divot in the bleak Martian plains, in the hope that it will survive to plumb the geological history that's written into the crater walls.

"The rovers are getting older," said one mission leader. "It's kinda like sending your grandmother down the steep slope. You think she can make it, but you're a little concerned she might slip and fall and injure herself."

Click here for more. And here's some video about the decision.

You can see MArs with your own eyes if skies are clear and you're willing to step outside in the wee hours of the morning. The red planet is rising in the southeast this week just before 2 a.m. Tomorrow, the 4th, marks the winter solstice on Mars.

For more stellar fireworks in the sky, check this out. It's the latest from the Hubble Space Telescope.

Posted by Frank Roylance at 9:54 AM | | Comments (0)
Categories: Cool pictures

July 2, 2007

Pax River NAS, from space

The crew of the International Space Station in April captured an interesting shot of the Patuxent River Naval Air Station in Southern Maryland. The astronauts like to use the airbase's crossed runways as a sort of test pattern for fine-tuning their cameras. Have a look.

There's another orbital photo of Maryland out this morning. It was taken Sunday by one of NASA's Earth-observing satellites. Click here. It was a beautiful day whether you were looking up from Maryland, or down on it. Here's one more, taken Monday by NASA's Terra satellite. Clear skies all around the state.

Speaking of looking up, here's one of the most amazing pictures ever taken of the International Space Station - from the ground!  It was snapped a couple of weeks ago while the shuttle Atlantis was docked to the station. 

Posted by Frank Roylance at 1:31 PM | | Comments (0)
Categories: Cool pictures

Blanket night

If you had your windows open last night you probably found yourself reaching for a blanket by first light this morning. The low temperature at BWI-Marshall was 59 degrees this morning. That was six degrees below the long-term average low for the date, but well short of the record low for a July 2 in Baltimore - 51 degrees set way back in 2001. Blankets in July are a good thing. They mean the AC is off and BGE's electric meters are barely turning.

It was 52 degrees at dawn on the WeatherDeck in Cockeysville, but a comparatively mild 63 degrees here at Calvert & Centre streets. Here are some overnight low readings from around the region: 

BWI: 59 degrees

Frederick Airport: 48 degrees

Dulles International: 59 degrees

Martin State Airport: 57 degrees

Ocean City: 55 degrees

Dover, DE: 53 degrees

Harrisburg, PA: 51 degrees

We can thank a Canadian high-pressure system for the cool, dry weather. And we'll have one more chilly night tonight, with a forecast low of 58 at BWI and good stargazing.

The high is moving from the Great Lakes south and east to the Atlantic coast. As the center gets past us, we'll fall once again under the return flow, which will bring winds from the South. And that means warming temperatures and rising humidities Tuesday night into Wednesday.

The Fourth should be hotter, but seasonably so, with highs at BWI in the upper 80s. We should not see any 90s this week, if the forecasters are right. Another cold front will droop south across the Mid-Atlantic states by Friday, bringing another chance for some showers. But don't look for any real relief from the persistent dry weather.

The forecast calls for temperatures to rise gradually during the week, with a slowly increasing chance of afternoon showers and thunderstorms. The weekend looks dry and pleasant.

Posted by Frank Roylance at 10:57 AM | | Comments (0)
Categories: By the numbers

July 1, 2007

Waterspout? Dust devil?

Readers: Did anyone else spot anything like this in Harford County Saturday? Did anyone get a picture? If so, email it to me at  Thanks.

"Mr Roylance,

"My wife and I were driving westbound on US40 this afternoon (Saturday, 30 June), at about 1:45 PM.  As we approached MD 543 in Belcamp (in Harford County) I noticed a thin, dark, mostly vertical column of SOMETHING rising from the vicinity of the Bush River toward the sky.  I could not tell what it was, but I definitely saw this thing, and my wife saw it too.  It did not last very long, and it eventually faded completely away.  It almost looked like a shadow, but it moved and bent a little before it faded.  It did not look like any kind of smoke that I have ever seen.  We thought it sort of looked like a big, thin, dust devil.

"The sky was fairly clear, with no storm in the area, and no weird winds were obvious from where we were driving. Could this have been a small waterspout?  Were the conditions today right for a waterspout to form?  I know from a TV weather show that waterspouts form in a different way than regular tornadoes, and they are much weaker.

"Unfortunately, I did not have a camera on me at the time. Sincerely, Monroe Harden, Havre de Grace, MD"


Posted by Frank Roylance at 11:08 AM | | Comments (0)
Categories: Observer reports
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About Frank Roylance
This site is the Maryland Weather archive. The current Maryland Weather blog can be found here.
Frank Roylance is a reporter for The Baltimore Sun. He came to Baltimore from New Bedford, Mass. in 1980 to join the old Evening Sun. He moved to the morning Sun when the papers merged in 1992, and has spent most of his time since covering science, including astronomy and the weather. One of The Baltimore Sun's first online Web logs, the Weather Blog debuted in October 2004. In June 2006 Frank also began writing comments on local weather and stargazing for The Baltimore Sun's print Weather Page. Frank also answers readers’ weather queries for the newspaper and the blog. Frank Roylance retired in October 2011. Maryland Weather is now being updated by members of The Baltimore Sun staff

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