baltimoresun.com

« January 2007 | Main | March 2007 »

February 28, 2007

Big rain, flood watch up

That storm brewing out over the Texas panhandle is set to slide this way tomorrow, drawing plenty of moisture and warm air out of the Gulf of Mexico. That will mean as much as an inch of rain here late Thursday into Friday.

UPDATE 7:00 A.M. THURSDAY:  The flood watch has been extended to all of Maryland west of the Chesapeake. Locally heavy rains could drop 1 to 3 inches in some locations. Frozen soil just below the surface could increase runoff and stream flooding. Here's the new flood watch.

EARLIER: That's a lot of rain, but forecasters say they're not too worried about flooding. Most of our remaining snow cover is gone. So a meltdown in heavy rain is no longer an issue. Similarly, the ice that formed in area streams during February's cold weather is mostly gone, so there's little danger of ice jams causing unexpected flooding here. If rains exceed two inches flooding might be an issue, they say. But that doesn't look likely.

Catawissabrdigeicejam00 The same cannot be said for Pennsylvania counties to our north. The weather service has issued flood watches across much of PA, as well as Garrett and Cecil counties in Maryland. where heavy rain, wind, lingering snow pack and river ice threaten to combine to raise streams. That would break the ice and could lead to ice jams that might bring streams above flood levels. Here's the River Forecast Center's take. The photo shows the Catawissa Bridge over the Susquehanna River in Bloomsburg, Pa. as it was knocked from its piers by an ice jam in March 1904.

Elsewhere, severe storms, tornadoes and blizzard conditions are expected to accompany this storm as it moves east. Here's AccuWeather on the subject.

Posted by Frank Roylance at 5:22 PM | | Comments (0)
Categories: Forecasts
        

February 27, 2007

Now La Nina, and hurricanes

The National Oceanic and Atmospheric Administration says rapidly cooling surface waters in the eastern and central tropical Pacific are signaling the approach of another La Nina event. And with La Nina comes an increased likelihood of Atlantic hurricanes during the coming season. Read more here.

One reason the 2006 hurricane season fizzled was the unexpected arrival of an El Nino event - a warming of the Central and Eastern tropical Pacific. El Ninos tend to suppress Atlantic hurricanes by creating wind shear that decapitates the storms before they get well organized. Other factors, including dust blowing out over the Atlantic from Africa, also kept the hurricane count low last summer. (El Ninos have other impacts around the world, including drought and wildfires in Indonesia.)

La Ninas suppress hurricanes in the Pacific, but do the opposite for the Atlantic basin. Again, other factors come into play, too. But La Nina may be one that contributes to this year's storm count. Famed hurricane forecaster William Gray was predicting a more active 2007 storm season even before conditions began edging toward a new La Nina. Here's his forecast, issued in December. It includes the increased probabilities for East Coast landfalls in 2007.

Posted by Frank Roylance at 6:02 PM | | Comments (2)
Categories: Hurricanes
        

Valentine's Day storm a Cat. 3

The snow and ice storm that struck Maryland and much of the Northeast and Midwest on Feb. 13-14 has been classified as a Category 3 "Major" event on the new Northeast Snowfall Impact Scale (NESIS). The scale was developed to rank and compare Northeast snowstorms based on snow depth, area and the population affected.

Snowmap According to the analysis that led to the ranking, the 2007 Valentine's Day storm was among the top three storms affecting the interior regions of the Northeast since 1940, and 14th among the 34 worst storms in the Northeast since 1950.

Although the Baltimore-Washington area saw no more than a few inches of snow in this storm (2.7 inches at BWI), there was plenty of ice south of Baltimore, and more than 100,000 BGE customers lost power at some point during the bad weather. One to three feet of snow fell in interior portions of New York, Pennsylvania and New England.

To read more about the NESIS ranking for this storm, click here. And here's an extended description of the NESIS scale.

Posted by Frank Roylance at 5:16 PM | | Comments (0)
Categories: Winter weather
        

Kiss the snow ...

... goodbye. Between this week's rising temperatures and sunshine, and the substantial rain forecast for Thursday and Friday, we should be rid of all this stuff (save for some stubborn plow piles) by the weekend.

We're headed for the 50s by the week's end. It will cool some after the rain and the arrival of a cold front on Friday, but not enough to worry about frozen precipitation. The rain will also rinse a lot of filthy cars - my own among them. And, if you don't think about where all those road chemicals and salt are going, the world around us will be generally cleaner for the dousing. Forecasters say we could get as much as three-quarters of an inch of rain before it's over. Anyway, here's the official forecast.

Keep your eye on the forecast for Saturday evening. There's a total eclipse of the moon on tap for the hours immediately after sunset, and we need clear skies to the east. So far they're predicting partly cloudy skies. More about the eclipse in The Sun in the coming days. If we miss this one, there's another in August.

Posted by Frank Roylance at 8:16 AM | | Comments (0)
Categories: Forecasts
        

February 26, 2007

So, who blew the forecast?

It was beautiful snow, perfect for a walk in the woods with your honey, which is where I was. But it was also a surprise. Forecasters had been predicting a little snow, followed by a bunch of sleet, freezing rain Sunday as warm air from the southwest overran a stubborn wedge of cold air at the surface. Ice accumulations on trees and wires were expected to cause more power outages.

Sundaysnow In the end, it snowed for much of the late morning and early afternoon across a lot of the region. Accumulations ranged from about 5 inches in Columbia down to just a few elsewhere. Or none to the south and east. Here's a preliminary report. And here's a mapped version. We had 3 inches and change on the WeatherDeck, followed by some sleet and rain late in the day.

The snow, as pretty as it was, was not what we expected.

Pete Binco wrote: "Since you are the face of The Weather Page, my question is who made the forecast for Sunday (Freezing rain, sleet) and the Maryland & Region freezing rain and sleet to the area with no mention of snow anywhere in forecast? " 

David Gerstman wrote: "I know a lot of people are going to criticize the forecasters for getting today's weather wrong, as we were getting snow... not ice. Over the years, though, it's seemed to me that the one thing that forecasters get wrong more than anything is the speed with which a system moves. Of course, a slow-moving system (such as this one) might have different results (colder air up high causing snow). Am I right that predicting the speed of a storm is the toughest part of meteorology?"

Here's what I know: I spoke this morning with Steven M. Zubrick, science and operations officer at the NWS forecast office in Sterling, Va., which is responsible for forecasts in the Baltimore/Washington region.

"I'm not defensive about it," Zubrick said of the forecast. "Given all the information we had on Saturday, would I do it again? I probably would ... I'd probably put more snow in, definitely. But not that much, because all the indications were that it would be well above freezing aloft."

Except it wasn't. The air aloft got colder and wetter, faster, than the computer models predicted. "Whenever you have rapid changes, the models don't adjust to rapidity very well," he said.

Specifically, Zubrick said, the Sterling office released a weather balloon at 1 a.m. Sunday morning, and it reported the atmosphere at 10,000 feet was "completely dry." The next balloon, at 6 a.m., reported the air up there was "completely saturated."

Evaporation of the arriving moisture as it hit that dry air caused it to cool, in the same way that evaporation off your skin in hot, dry weather makes you feel cooler. Instead of 40 degrees aloft, it was right around freezing. So when the air became saturated, it began to precipitate - as snow. And the air stayed cold enough to support snow for hours.

Another factor called "banding" further concentrated the moisture and created vertical motion that brought even more cooling and more precipitation. More snow. The models were wrong.

"If we were just looking at one model, that would be one thing," Zubrick said. "But we were looking at a collection of models" and other tools. "All the guidance was suggesting we would definitely have warm air aloft ... It turned out to be colder."

And maybe it was all for the better, he added. "With all due respect, I think it (the snow) was better for all involved." Better, that is, than an ice storm with trees and power lines down. Highway officials were all well-briefed for ice, so the roads were all well-salted, and the morning rush hour went better than it might have had the forecast called for snow, and turned out to be ice.

Forecasters, conscious of the possibility that the storm could deliver more snow than expected, also decided not to change the "Winter Storm Warning" (which implies 4 inches of snow or more in 12 hours) to a "Ice Storm Warning" (which implies a quarter-inch of icing).

So, what about David Gerstman's question? Is the speed or timing of a storm the toughest part of meteorology?

"That's like saying, 'Is putting the hardest part of golf?'" Zubrick said. Timing is a challenge, but so is predicting moisture content. And storm intensity.

In the end, weather forecasting is a mind-numbingly complex business, with zillions of variables and myriad laws of physics to consider in your forecasts.

"It would be impossible for me to run those equations in my head," Zubrick said, "I can't do what a computer can do, so I rely heavily on what the computer is doing, putting more and more details into the physics."

At the same time, the data the computers have to work with is limited. "It's not like we have sensors on every block. We'd have to have them going all the way up into the sky. We're doing very well with improving remote sensing techniques, and getting them into a model." 

But it's not a perfect science.  "Ball players don't bat 1.000," Zubrick said. "Sometimes we get curves, and we do the best we can. Overall, we did a fine job. Everyone knew it was happening. The trucks were treating the roads, and people were able to get out."

Posted by Frank Roylance at 11:56 AM | | Comments (0)
Categories: Winter weather
        

February 25, 2007

Headed for 50

Sure it's a mess out there. But look on the bright side: The storm is departing. The forecast shows us headed through the 40s to 50 degrees, with increasing sunshine, this week. And all this slop will melt away pretty quickly. Here's the official forecast. 

At this time of year, the average high temperature is gaining a degree every three or four days. We're not totally out of the winter weather woods. Two of the 10 deepest snowfalls in Baltimore history have occurred in March. But we're headed in the right direction. And the start of Daylight Saving Time is just two weeks away. Really.

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

Snow forecast pushes 10 inches

Forecasters will have some 'splainin' to do when this storm is over. What had been forecast to be little more than a nasty ice storm is turning into the biggest snowfall of the season. As much as 10 inches is now forecast for the Baltimore and Washington regions, with the deeper amounts to the north and west, less to the south and east.

Already this afternoon the winter storm warning zone has been shifted farther to the south and east to include Anne Arundel County. Here's the warning language for the city, Baltimore, Harford, Carroll and Howard counties:

"TOTAL SNOWFALL WILL BE 5 TO 10 INCHES BY THE TIME THE SNOW ENDS
IN MOST AREAS. ISOLATED LOCATIONS IN THE HIGHER TERRAIN WILL SEE
UP TO ONE FOOT OF SNOW...SUCH AS ALONG THE BLUE RIDGE AND
ALLEGHENY FRONT. THERE WILL ALSO BE A CHANCE OF LIGHT FREEZING
RAIN THIS EVENING UNTIL ABOUT MIDNIGHT."

Here's how it's worded for Arundel:

"PERIODS OF MODERATE TO HEAVY SNOW WILL CONTINUE THIS AFTERNOON AS
LOW PRESSURE BEGINS TO DEVELOP NEAR THE DELMARVA.

TOTAL SNOWFALL WILL BE 4 TO 8 INCHES BY THE TIME THE SNOW ENDS
EARLY THIS EVENING...EXCEPT IN WASHINGTON DC WHERE SNOWFALL WILL
BE 3 TO 6 INCHES. THERE WILL ALSO BE A CHANCE OF LIGHT FREEZING
RAIN THIS EVENING UNTIL ABOUT MIDNIGHT."

We're already past 2.5 inches here on the WeatherDeck. The roads, just wet until a couple of hours ago, are now snow-covered. But the radar loop would suggest the precipitation won't last too much longer. Frederick Airport is reporting light rain at 2:30 p.m. BWI reports heavy snow.

Don't forget to post your BEST snow photos on the Reader Photo Gallery, found at the bottom of the main page at MarylandWeather.com

For some insight into the forecasters' thinking this morning, here's their forecast discussion, from 6 a.m., with a late-morning update. They appeared to be faced with conflicting computer model forecasts, and found themselves having to boost their snow estimates to synch up with the implications from weather-spotter reports of heavier-than-expected snowfalls in Virginia.

Update, 3:50 p.m.:  It's sleeting now on the WeatherDeck. Total snow accumulation is about 3.2 inches.

Posted by Frank Roylance at 2:29 PM | | Comments (0)
Categories: Forecasts
        

Two to 5 inches NW of I-95

The snow is falling pretty well now on the WeatherDeck in Cockeysville. It seemed a bit late in arriving given all the hype yesterday and overnight. It appears to be sticking to the grass and walks, but the streets, still salty from the last storm, appear just wet.

Temperatures have dropped a bit this morning, falling just below freezing on my instruments. The forecast for communities north and west of I-95 is snowier than for those to the south and east.

Here's the "winter storm warning" for Timonium and Lutherville, and the official forecast:

"A MIXTURE OF SNOW AND SLEET WILL CONTINUE THROUGH THE
AFTERNOON...HEAVY AT TIMES. THE WINTRY PRECIP WILL CHANGE TO A MIX
OF FREEZING RAIN AND SLEET EARLY THIS EVENING. EXPECT AN
ADDITIONAL 2 TO 5 INCHES OF SNOW AND SLEET THROUGH THE AFTERNOON
BEFORE THE TRANSITION TO LIGHT FREEZING RAIN. ICE ACCUMULATIONS
ARE EXPECTED TO BE ONE-QUARTER INCH OR LESS.

THE BULK OF THE FREEZING PRECIPITATION WILL TAPER OFF BY MIDNIGHT
IN MOST AREAS.

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW...
SLEET...AND ICE ARE EXPECTED OR OCCURRING. THIS AMOUNT OF GLAZE
COULD CAUSE WIDESPREAD DOWNED TREES AND POWER LINES RESULTING IN
POWER OUTAGES AND HAZARDOUS TRAVEL."

By way of contrast, here's the "winter weather advisory" for Severn, in Anne Arundel County:

"A MIXTURE OF SLEET...FREEZING RAIN AND RAIN WILL CONTINUE THROUGH
THIS EVENING. ADDITIONAL SLEET ACCUMULATIONS WILL BE LESS THAN AN
INCH AND ICE ACCUMULATIONS WILL BE LESS THAN ONE-QUARTER INCH.

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...SLEET...OR
FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING."

Here's how the "storm warning" and "weather advisory" territories sort out. And here's the northeast radar.

Posted by Frank Roylance at 11:35 AM | | Comments (0)
Categories: Winter weather
        

February 23, 2007

More ice on the way. Sorry

The National Weather Service has issued a Winter Storm Watch for most of Maryland west of the Chesapeake Bay as (another) low-pressure system lumbers in from the Great Plains.

Once again, the Baltimore region does not appear to be in line for significant snowfall. But an accumulation of ice - up to a quarter-inch - on Sunday does appear to be in the cards, just as parts of the region warm up again after days without power as a result of last week's ice storm. Sigh...

Here's the Watch, posted this afternoon. Here's the map. And here is AccuWeather again on the ice threat.

Posted by Frank Roylance at 2:58 PM | | Comments (0)
Categories: Forecasts
        

Got your BGE bill? Yeow!

My gas and electric bill arrived yesterday, covering the period from mid-January to mid-February. That was the coldest part of the winter so far. Temperatures, according to the bill, averaged just 27 degrees. That compared with 40 degrees for the prior billing period, which was unusually mild.

Anyway, the bottom line took my breath away. My wife and I used twice the gas and electricity we used in the prior period, and our bill topped 250 bucks, easily the biggest BGE bill we've seen in nearly 10 years in this house. (That includes everything, not just the gas and electricity used for heating. But I presume the bulk of it was for heat.) If it hadn't been for the "credit" engineered by the legislature last year (which we'll all have to pay back eventually), the total would have been $333.  Gak!

Needless to say we switched off the electric blanket last night and threw another wool afghan on the bed. But the cold weather, coupled with sharply higher rates this winter compared with last winter, will take a toll on our budget this month. How about yours?

Here are the numbers behind the increased energy demand this month, from the National Weather Service. I'm comparing February (to date) with January, which does not exactly match my BGE billing period, and likely won't match yours either. Data is for BWI. Heating degree days are a measure of heating energy demand. Higher numbers reflect greater need for heat; lower numbers reflect less demand.

January average temperature : 38.7 degrees, 6.4 degrees above average.

February average temperature:  27.2 degrees, 7.6 degrees below average.

January heating degree days:  805, or about 19 percent less than average for January. (We should have burned that much LESS energy.)

February heating degree days:  827, about 26 percent more than average for February.

For the entire heating season to date, at least, we are still running on the good side, about 8 percent below the long-term average for Baltimore, thanks to a mild December and January. But that edge will erode if the weather stays cold.

Posted by Frank Roylance at 11:40 AM | | Comments (8)
Categories: By the numbers
        

A wintry-mix weekend

Sure it's cold and windy. But you may want to enjoy this sunny, dry, blustery, late-winter day, because once this high-pressure system moves off the coast tomorrow, we're in for another spell of snow, sleet, freezing rain, and rain on Sunday as another winter storm moves into the Northeast.

The really wintry weather will stay to our north. Forecasters say warmer, wetter air will begin moving into the region on Saturday behind the departing cold, with the advance of a low-pressure system from the Plains passing to our north.

Sometime after midnight Sunday, the precipitation will begin as snow, sleet and freezing rain. That will change over to rain on Sunday, except in the northern counties, where the messy mix is expected to linger into the afternoon. Here's AccuWeather on the ICE threat. Remember ice?

Rain Sunday evening may switch back to snow before it ends Monday. Here's the official forecast.

In the meantime, northwest winds around the approaching high have been blowing hard all night. They gusted as high as 35 mph around 1 a.m. here at The Sun. Out at BWI, they clocked gusts as high as 53 mph after midnight. Dulles Airport saw gusting to 45 mph.

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

February 22, 2007

This is so cool ...

Febsnow Here's a God's-eye view of the results of last week's snow and ice storm in the Northeast, from Virginia to Maine, including the Chesapeake Bay and Lake Ontario. You'll have to scroll some to find Maryland, but the satellite photo shows very clearly who got white stuff and who didn't. Click here and enjoy.  Thanks to the Goddard Space Flight Center and to Bruce Sullivan, of COCORAHS.

Posted by Frank Roylance at 5:02 PM | | Comments (0)
Categories: Cool pictures
        

Tie down Toto

Better put a rope on Toto today. Also bring in the garbage cans, secure your trash and put some muscle at the wheel of the Winnebago. Big wind's coming this afternoon as a cold front reaches the area from the northwest.

The National Weather Service has issued a wind advisory, warning of winds gusting in excess of 45 mph after the front reaches the I-95 corridor. Here's the advisory.

While our MarylandWeather.com forecast made mention of a possibility of thunderstorms arriving with the frontal passage, the National Weather Service discussion this morning downplays the possibility. We'll all find out in a few hours.

Behind the front we get into colder, drier air - colder than yesterday's highs in the 50s, and colder than the long-term averages for BWI at this time of year. But we won't be seeing the sort of arctic cold we saw last week, with lows in the teens and highs struggling to reach 30 degrees. Here's the official forecast.

Posted by Frank Roylance at 7:45 AM | | Comments (0)
Categories: Watches and warnings
        

February 21, 2007

Another spacecraft blows up

Skywatchers in Australia were startled Monday night to see a slow-moving, comet-like object appear in the night sky, and then flare as if something had blown up. A mystery for days, it has finally been identified as the explosion of an old booster rocket. Read more about it here.

It's a problem well-known to those who monitor orbiting space craft and space junk. As old booster rockets deteriorate in space, leftover fuel and oxidizer - normally kept separate until the rocket is fired - break through seals, and combine explosively. The blasts shatter the rockets and scatter hundreds of new pieces of space debris.

International protocols have been issued to minimize such events. Mission designers are supposed to reserve enough fuel to send obsolete spacecraft to burn up in the atmosphere before such accidents can occur, or park them in harmless, out-of-the-way orbits where they won't cause problems for active spacecraft. But older rockets and defunct objects launched before these protocols took effect - and new ones that get out of control or break down prematurely - can still cause problems like this one over Australia.

But old junkers and accidents are one thing. Deliberately turning one piece of space junk into thousands - deliberately - is quite another.

It was only last month that the Chinese tested a satellite-killing missile on one of their obsolete weather satellites. In addition to proving they could knock out satellites (presumably an enemy's spy satellites), they also scattered more than 700 new pieces of space junk big enough to track (and likely thousands of smaller, but still hazardous ones), infuriating the space-faring community. All those shards have now become potential hazards to every nation's spacecraft, both manned and unmanned.

Posted by Frank Roylance at 7:35 PM | | Comments (0)
Categories: Sky Watching
        

Lake-effect snow on the bay?

As the mercury at The Sun this morning creeps toward 50 degrees, it seems safe to talk a bit about snow. Someone has asked whether lake-effect snow - the sort that has swept off Lake Ontario this winter and buried parts of western New York State - could occur on a body of water the size of the Chesapeake Bay.

The short answer is yes. It's been studied and deemed possible. But it is, apparently very rare. Here's a clip from the Virginia Pilot on an event in 1996. Researcher Crosby Savage, at North Carolina State University, has even found a radar image of such an event in 1999. The target that day was Norfolk.

Lake-effect (or "bay-effect") snow occurs when cold winds sweep across large bodies of relatively warm, open water. Along the Great Lakes, blasts of arctic air blow across the open lakes, pick up moisture, which is then lifted higher by the higher terrain on the lee of the lakes - Ohio, Pennsylvania and New York mostly. As it rises, the air cools, and the moisture condenses, freezes and falls as snow.

The Chesapeake is smaller than the Great Lakes, of course. And the surrounding terrain - especially on the lee side in a north wind - is generally flat. But scientists have concluded the conditions are sufficient to sustain a bay-effect snow.

To read more than anyone could possibly want to read on the topic, click hereAnd here.

Thanks to AccuWeather for the links.

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

February 20, 2007

New star in morning sky

The titanic explosion of a faraway star has put a new light in the early morning sky. Astronomers are reporting the "nova" has temporarily reached naked-eye brightness. It's visible from dark locations, in the southeastern sky before dawn, although clouds may interfere if this forecast holds.

Look below brilliant Jupiter using this star map. Binoculars will make it easier to see where urban light pollution obscures the view. Don't wait to look for it. As the explosion expands, this nova will fade. Here's how it looked recently to amateur astronomers in Iran.

Nova Here's a Hubble-eye view of another stellar explosion, this one involving a star much like our sun. It reveals the ultimate fate of our star, and our solar system, including all life on our home planet. Sorry.

Posted by Frank Roylance at 7:02 PM | | Comments (0)
        

Rain, temps battle ice

Mild air streaming out of the Gulf states today is driving temperatures into the more seasonable range for this time of year in Baltimore. At last. We may even rise above normal this afternoon for the first time in a long time. It's already 45 degrees here at The Sun building, about the normal high for a Feb. 20 at BWI. That's the first time we've seen 45 degrees here since Jan. 28 - three weeks.

For now, we remain within the white zone on the snow-cover map. Here's the 31-day loop.

There's more mild weather in the forecast, and rain, too. We could see a little rain this evening or tonight, with more likely late Saturday and Sunday.  All of that will go far toward ridding us of this thick, stubborn, dangerous coating of ice left behind by last week's storm. Frederick schools had another delayed opening this morning because of the thick ice that remains on area sidewalks out there.Icemap  This map of last week's snow and ice accumulations gives you an idea as to why Frederick is still struggling.

Hydrologists aren't worried about flooding as the rising temperatures and rain go to work on the remaining snow and ice. Not enough of it to flood, and streams are running low enough that there's plenty of room within their banks.

That's not to say it wouldn't be smart to clear a path to your nearest storm drains if there are heaps of ice blocking drainage. A little chopping now may prevent a lot of mopping later on.

In the meantime, forecasters are beginning to pay attention to a major storm on tap for the eastern two-thirds of the nation this weekend. Our piece looks like heavy rain only. But we'll be reading and watching news of heavy snows on the Plains and well to our north, and tornadoes to our south and southwest. Overall, the weather patterns are beginning to look more spring-like.

And why not? Daylight Saving Time begins in three weeks, a full 10 days before the official end of winter.

And by the way, our comments fields are working again. Feel free to express yourself.

Posted by Frank Roylance at 10:34 AM | | Comments (0)
Categories: Winter weather
        

February 16, 2007

The Big Snow, four years gone

You think this week's snow-and-ice storm has been a pain? Think back to where you were exactly four years ago today, and you may find yourself in the middle of a four-day snowstorm that dropped 28 inches at BWI - nearly 22 inches of it on the 16th. The region was paralyzed by the biggest snowfall in the city since official snow record-keeping began in 1883.

2003snow That February was and still is the snowiest on record, with 40.5 inches of snow. The winter of 2002-2003 ended as the second-snowiest, with 58.1 inches. The record-holder remains 1995-1996, when 62.5 inches fell. The average seasonal total for Baltimore for the 30-year period from 1971-2000 is just 18 inches.

Here's a link to The Sun's coverage of that monumental 2003 winter storm in stories and pictures.

Here's the National Weather Service's ranking of the top 10 winter storms for our region.

And here's a narrative description of all the major winter storms here since Thomas Jefferson was a pup.

Posted by Frank Roylance at 3:51 PM | | Comments (0)
Categories: History
        

Starry night, weekend flakes

Continued cold temperatures and a series of "clippers" zipping down from the northwest this weekend could add some snowflakes to the scene as we work to chip our way out of the mess left behind by this week's storm. The good news is that the clippers are fairly dry, and what moisture they do have is falling through more dry air. So much, or all, of the snow they generate may evaporate before it reaches the ground.

So keep on chipping. Or, if you have no place to go, sit tight and wait for warmer temperatures - maybe even RAIN - next week. Here's the official forecast.

In the meantime, skies have cleared nicely, and tonight promises to be a great night for stargazing. That's Venus gleaming in the western sky after sundown. Mercury, which was close by last week has since moved down into the sun's glare. NASA's Messenger spacecraft, built and controlled at the Johns Hopkins Applied Physics Lab near Laurel, is on its way to a 2011 encounter with Mercury.

Saturn Saturn rises in the east at sunset. To find it, face due east after dark. Look for a bright, pale yellowish "star" just above the eastern horizon, perhaps a bit north of due east. Don't confuse it with the brilliant star Sirius, higher and more toward the south.

You can't see Saturn's distinctive rings without at least a small telescope, but if you get the chance, take it. The first time is always the best. The Cassini spacecraft is still circling Saturn and its moons.

Jupiterearthspot_comparison And, if you're up early tomorrow, look to the southeast. The brightest "star" in that part of the sky just before dawn is the giant planet Jupiter. (Here's an image comparing the size of Jupiter's "great red spot" with the Earth.) A decent pair of binoculars and a steady place to rest them will reveal as many as four of its largest moons, lined up on either side of Jupiter like tiny planets. They're the same moons Galileo first spied with his telescope on Jan. 7, 1610. APL is also shepherding a spacecraft past Jupiter this month. It's the New Horizons mission, bound for Pluto.

Posted by Frank Roylance at 10:46 AM | | Comments (0)
Categories: Forecasts
        

February 15, 2007

January was globe's warmest

January 2007 clocked out two weeks ago as the warmest January on record around the globe, according to the National Oceanic and Atmospheric Administration. For the United States, it was just average. Read more about it here.  For Maryland, January averaged 38.7 degrees. That was 6.4 degrees above the long-term average for a January at BWI.

February, on the other hand, is running very cold. We've averaged just 25.6 degrees through Wednesday at BWI. That's 8.3 degrees below the long-term average, and tied with 1979 for the second-coldest February on record for Baltimore, going back to 1871. The coldest February on the books was in 1934, when the city averaged just 24.3 degrees.

It's costing us money. We're running 28 percent ahead of normal on heating degree-days so far this month. That means we've called on 28 percent more heating energy than the long-term average. Still, for the heating season so far, we remain ahead of the game by about 10 percent, thanks to a mild December and January.

We still have half the month to run, of course, and we're headed for the mid-40s next week - a shade above the norms. By the 28th, this month may well have faded back into temperature obscurity.

Note to Readers: We are still seeking a solution to a software problem that is preventing WeatherBlog readers from filing comments. The program just won't load the comments field. The solution is way beyond my pay grade, but we have people in Baltimore and Chicago and elsewhere wrestling with it.

Thanks for your patience. If you want to email me directly with your comments, feel free. Just click on the "froylance" link below. I'll post them directly to the blog as quickly as I can. That, at least, still works.

Posted by Frank Roylance at 4:08 PM | | Comments (0)
Categories: Climate change
        

Ice like iron

Snow, sleet and freezing rain, followed by overnight lows in the teens have combined to turn the ice out there to iron. I watched a neighbor this morning, on her haunches at the end of her driveway, whacking away at the mound of ice that blocked her escape - with a HAMMER!  It's that hard.

My wife, a teacher, was outside yesterday while the snow and ice were soft, and shoveled off the steps and the sidewalk. And she cleaned off her car. But she's a delicate thing, so she didn't shovel out the ice mound that county plows piled up behind the car.

OK. It's not that high. Maybe 4 or 5 inches. But by this morning it was as hard as a concrete curb. I tried stabbing at it with the shovel, but it bounced off. It was impervious to my stomps. And when I tried to drive her car over it, it might as well have been a Jersey wall.

Fortunately, I left my car on the street last night after trying to drive over the same mound and nearly hanging the car up by its undercarriage. So I made it to work. But she's stuck. I'll have to chip away at that thing tonight with the ice chipper until it gives way, or pray the schools are closed for one more day.

Meanwhile, the cold weather persists. We reached 15 on the WeatherDeck in Cockeysville overnight. It was 18 degrees here at The Sun, where winds gusted to 24 mph overnight. And the thermometer dipped to 16 at BWI.

If we hope to get rid of this ice in the next few days, we'll have to rely on sunshine, salt, sweat and sublimation, because the temperatures won't help much. The NWS forecast calls for highs of just 35 degrees through the weekend, after overnight lows in the teens and 20s. We won't see 40s - normal for mid-February - until Tuesday or Wednesday of next week. In fact, our weather for the next day or two looks kinda like the forecast for this place.

So, what's happened to global warming? Well, this is about weather. Our weather. And global warming is about climate - and long-term global averages. And there's plenty of data about where those are headed. Here's a sample.

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

February 14, 2007

Winds up, temperatures down

As forecast, the temperatures in Baltimore this afternoon have begun to fall, and the winds (and the barometer) are picking up as the offshore low begins to intensify and move away.

The mercury here at The Sun has slipped from 37 degrees at 2 p.m. to 31 degrees just before 4 p.m. And it has far to go. The forecast low for BWI tonight is just 15 degrees, 11 degrees colder than the normal low for this time of year.

The barometer has turned a corner, too. It's headed up from a low of 29.41 inches at 9 a.m. Watch the storm pull away on this Northeast radar loop.

Winds here at The Sun are averaging about 12 mph, with gusts to 35 mph from the west. They're blowing even harder out at BWI-Thurgood Marshall Airport. The winds are being pumped up by the clockwise spin of the high centered over Nebraska on this weather map, and the counterclockwise spin of winds around the low in northern New England. Together, they form a wind chute between them that's blowing all over us.

Then again, it's not as bad as on top of Mt. Washington in New Hampshire, where the temperature is 4 degrees, with winds gusting to 71 mph. That makes the wind chill minus-28 degrees.

For readers who have tried to post comments without success, our apologies. Our blog host's software is hanging up and won't load the comment field. We're working on it.

Posted by Frank Roylance at 3:56 PM | | Comments (0)
Categories: Winter weather
        

Next storm?

We're still dealing with the fallout from this Valentine's Day Ice Storm, and already we're hearing whispers (or is it whimpers?) about another storm head our way for President's Day weekend - a familiar time for big snowstorms around here.

Well, there are computer models out there that suggest that a disturbance due here over the long weekend - a fast-moving, not-very-wet "clipper" like the one that gave us a dusting last week - could spin off a secondary low at the coast. That low would then intensify and give us a more significant storm as it turns up the East Coast.

So far, the forecast shows just a 30 percent chance of snow showers on Saturday. For more on the weekend's prospects, check in with AccuWeather's snow-hawk, Henry Margusity. (Scroll down to "The Next Storm.") He says, with the cold still in place, and storms in the wings, "we're not out of this pattern yet." But even he doesn't seem to feel we need to worry about the weekend.

Posted by Frank Roylance at 1:06 PM | | Comments (0)
Categories: Forecasts
        

Not out of the woods

OK, so the snow, freezing rain and the sleet showers are mostly over. Here are some area measurements.  And the salt is working to reduce the slush  and ruts on the roads. But we are not yet quite done with this storm. The winter storm warning remains in effect until 1 this afternoon.

Hydrant The National Weather Service reminds us that the secondary low that is forming off the coast will begin to pull very cold arctic air down from upstate New York and Pennsylvania in the coming hours. It will get colder, and much windier, with gusts as high as 40 mph, making the cold seem even colder. We may even get another blast of snow.

Here's the Northeast radar loop, and the satellite view, showing the storm pulling away toward the north and east. And here's the official forecast. The rest of the week looks pretty darn cold, especially compared with the normals for this time of year. As you can see in the first column, the average high for a Feb. 14 at BWI is 44 degrees.

The higher winds will likely knock more ice-burdened tree limbs around, yank a lot of power lines beyond their breaking points and plunge many of us back into the dark. Here's how BGE is doing as their crews clean up last night's mess. Driving around a very slushy Beltway this morning (had to deliver a chocolate Valentine to my mom), it was evident that there was more ice in the trees on the south side compared with the north.

Speaking of the deepening low to our east, have you noticed your barometers this morning? My station on the WeatherDeck in Cockeysville touched off an alarm early today after the barometer sank nearly an inch in 24 hours. Here at The Sun, the barometer dropped from 30.34 inches at about this time yesterday, to 29.42 inches as I write this. That may be the bottom, as the low will soon begin moving off to the Northeast. But it was quite a plunge. Someday we hope to make our Sun data available here.

But for now, here's a link to the readings at BWI, via MarylandWeather.com  Just scroll down to the strip charts and look for the "barometric pressure" readings.

Got some really good digital snow/ice photos? Register for our Reader's Photos gallery and send them to us.

Did you have a ice-driving adventure this morning?  Leave a comment here and tell us about it. I had one - ice cascading down on my windshield, launched by a plow going the other direction on the Beltway. Very scary.

Posted by Frank Roylance at 10:44 AM | | Comments (1)
Categories: Forecasts
        

February 13, 2007

Meanwhile, blizzard to our west

While Central Maryland waits to see how this threatened ice storm develops, residents to our west, in Indiana and Ohio, are enduring what some say will be one of the worst blizzards on record out there. And more blizzard forecasts are being issued for the interior portions of New York and New England. We may get off comparatively easy.

Here's AccuWeather on the developing Midwest blizzard. And here they are again on what's in store for New England as the secondary low develops off the coast, and cranks up an old-fashioned nor'easter. Here, if you can get through, is the forecast for Glens Falls, NY, in the Adirondacks, which is facing 16 to 32 inches of snow tomorrow.

Posted by Frank Roylance at 2:21 PM | | Comments (0)
Categories: Winter weather
        

Heavy rain, freezing temps

That's a bad combination, but it's the fate in store for us this afternoon and evening. How's this for weird: Surface temperatures, now in the upper 20s, are going to fall this afternoon, but the light snow we're getting now will change over to moderate to heavy rain tonight as warmer air moves in thousands of feet over our heads.

Icycommute The result? Accumulating ice. Here's the latest from Sterling:

"A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 2 PM EST
WEDNESDAY.

PERIODS OF SNOW AND SLEET ARE EXPECTED THIS AFTERNOON. A CHANGE TO
FREEZING RAIN IS EXPECTED OVER MOST AREAS THIS EVENING.

SNOW AND SLEET ACCUMULATIONS TODAY ARE EXPECTED TO TOTAL THREE TO
FIVE INCHES OVER PORTIONS OF THE NORTHERN SHENANDOAH VALLEY AND
EXTREME WESTERN MARYLAND...WHILE ONE TO THREE INCHES IS FORECAST
OVER NORTHERN VIRGINIA AND NORTH CENTRAL MARYLAND
....AROUND AN
INCH IN THE I-95 CORRIDOR.
OVER THE HIGHLANDS AND CENTRAL
SHENANDOAH VALLEY...AN INCH OR LESS IS EXPECTED.

TEMPERATURES IN THE LOWER TO MID 30S ARE EXPECTED TO FALL DURING
THE AFTERNOON...AND BE BELOW FREEZING EVERYWHERE BY THE EVENING
COMMUTE...
AND REMAIN SUBFREEZING THROUGH MIDDAY WEDNESDAY.

TONIGHT MODERATE TO HEAVY RAIN IS EXPECTED TO DEVELOP. WITH
TEMPERATURES BELOW FREEZING THE SUBFREEZING AIR WILL CAUSE ICE TO
FORM ON TREES...ROADS...AND POWER LINES
. THE SHENANDOAH VALLEY
BETWEEN I-81 AND ROUTE 15 WILL BE ESPECIALLY
PROBLEMATIC...RECEIVING ICE TOTALS TONIGHT OF BETWEEN ONE QUARTER
AND THREE QUARTERS OF AN INCH. THIS WOULD CAUSE SIGNIFICANT
PROBLEMS WITH POWER OUTAGES AND TRAVEL.

ONE QUARTER TO ONE HALF INCH OF ICE IS EXPECTED FURTHER EAST.
TRAVEL PROBLEMS AND ADDITIONAL POWER OUTAGES ARE POSSIBLE IN THE
I-95 CORRIDOR OVERNIGHT.

See a good weather scene? Snow? Ice in the trees? Pets? Kids? Falling limbs? Snap it! And then log in to the Readers Photos gallery at MarylandWeather.com and upload it so we can all see.

Posted by Frank Roylance at 12:23 PM | | Comments (0)
Categories: Events
        

Ice is next

The snow started up right on schedule, and things are starting to look pretty wintry out there. But snow will not be the most memorable part of this storm. Forecasters continue to warn that this snow will gradually change to sleet and later to freezing rain today. As day turns to night, that could put a serious glaze on the world. There's talk of at least a quarter-inch of ice, and maybe up to a half inch in places.

Surface temperatures have been falling all morning. We've gone from 38 degrees at 5 a.m. here at The Sun, to 29 degrees now. But warm air is moving in aloft. That will melt the snow as it falls, but it will refreeze as it comes through the colder air near the surface, forming sleet or freezing rain.

If you could get to the National Weather Service Web site today - winter weather threatening the most densely populated part of the country seems to be causing some serious Web slowdowns this morning - you'd see that they're predicting the changeover to occur east of the mountains sometime this afternoon. Before then we could see an inch or two of snow accumulation, with 2 to 4 inches possible in Western Maryland.

Tonight we'll see mostly sleet and freezing rain in the I-95 corridor, fading to all-rain as you move south and east. But as a secondary low intensifies off the Carolina coast late today and tomorrow, it will begin to draw much colder air in from our north, changing the sleet/freezing rain/rain back to snow. That will put a dusting of snow on top of the ice. A slippery combination.

Be ready for power outages tonight as the ice builds in tree limbs and wires.

Stiff winds from the north early Wednesday, augmented by a waning moon and the lowest astronomical tides of the month, will cause unusually low tides on the Chesapeake. They're predicting "blowout" low tides on the bay, with low tides dropping a foot or two below predicted levels late Wednesday.

Here's AccuWeather's commentary on the storm. Here's this morning's discussion from the NWS forecasters at Sterling, if you can get through. Here's the national radar loop. And the Northeast loop.

I see school officials in Baltimore and Anne Arundel counties have reconsidered their decisions to open today. The kids are being dismissed three hours early. (For other school closing information, click here.) What forecast were they using?

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

February 12, 2007

Of mid-February snowstorms

Well, this storm isn't quite working out the way Baltimore snow-lovers might have wished. But it's going to snow hard somewhere. A slight change in the storm track and it could have been here.

The middle of February seems to be a favored time in these parts for big snowstorms. It's early enough in the season for cold, arctic air masses to become entrenched across the northeast, yet late enough for warm, wet storm systems to begin pushing far enough north to collide with the cold and unleash the snow machine in our laps.

Some of our biggest storms - indeed our very biggest - have come in the middle of February, between the 10th and 20th. We've had more than one "Presidents Day," "Presidents' Day Weekend," and "Valentines' Day" blizzard. Here's a list of the 10 biggest snowfalls for Baltimore and Washington from the National Weather Service. Notice that five fell between 2/10 and 2/20.

For some insight into Northeast snowstorms, read this interview with Louis Uccellini, director of the NOAA National Centers for Environmental Prediction and an expert on the topic.

One of the worst for Baltimore was a storm that ended on Valentine's Day in 1899. Sun researcher Paul McCardell pulled the clips from our newspaper for that storm. Here's a flavor of the coverage we gave that storm 108 years ago:

Headlines: "WORST BLIZZARD EVER KNOWN HERE; Business Paralyzed and Travel Suspended; 15.5 INCHES SNOW IN A DAY; Total Amount in Nine Days is 32.1 Inches, Breaking All Records - Many Persons Overcome by Cold - Freezing Weather in The South."

After an accounting of vacant streets, closed schools and stalled streetcars, the reporter went on...

"Suffering among the poor is becoming very keen, and nearly 3,000 persons applied at the police stations for aid. Generous contributions are being made for their support, but a great deal more will be needed. The Chinese of Baltimore contributed $100 to help relieve the poor."

In Washington, "The commissioners sent an urgent appeal to Congress for an appropriation of $20,000 to remove snow and ice from the streets and $5,000 to clear a channel in the Potomac. Two thousand men will be given employment."

"The whole South shivers, zero temperatures being reported in Georgia, Alabama, Louisiana and Kentucky, while Florida suffered with a freezing temperature. Damage to the fruit crops is expected."

"Thousands of persons in New York are starving and a bread famine is threatened."

In Baltimore, "There were few people on the streets who were not obliged to be there... Strong gusts of wind carried clouds of snow from the housetops and sent in whirling down into the streets, and other gusts caught the snow from the street and sent it whirling off to fall some other place... The unhappy pedestrian, plodding along, battling with snow in his face, would suddenly be brought to a stop by an unexpected plunge into a snow drift that would cover him almost to the waist...

"The snow would blow into the eyes, faces and down the necks of all alike, and then would melt from the heat of the body. Whirling along it piled up against the sides of houses and against fences, rendering the walking almost an impossibility."

The only effective communication was the still-novel telephone. But the Chesapeake and Potomac Company was struggling.

"The lines were kept going incessantly. Many of the operators became exhausted from the fatigue of answering calls and from the lack of food. One female operator at the central exchange, St. Paul street and Bank Lane, fainted from exhaustion."

Temperatures during all this snow climbed from 7 degrees, all the way up to 9 degrees before descending again. Winds blew at 30 mph. The effect on pedestrians was brutal.

"Miss Alberta Starr, aged eighteen years, an employee of the Gail & Ax tobacco factory, was overcome by cold on her way to her home, 1514 Boyd street, about 5 o'clock in the afternoon and sank in the snow unconscious at Light and Ostend streets. She was almost covered by snow when Patrolman Pfister saw her. He took her in his arms and hurried into Herman's shoe store with her. She recovered in about half an hour."

Another worker, a young man, the reporter continued, "started out in the morning with a freezer of icecream for a customer. After much struggling he managed to reach the customer's house, but while climbing out of the wagon was overcome and fell into a drift fully five feet deep, carrying the icecream freezer with him. He entirely disappeared from view, and a Mr. Lehmeyer, who saw the accident, rushed to the rescue with a large coal shovel. He managed to dig out the colored boy, who was nearly frozen."

One after another, The Sun detailed the near-death experiences of Baltimoreans trying to navigate the blizzard. A surprising number were rescued and taken to nearby drug stores for "restoratives."

Horses suffered, too. "Teams employed by business houses were scarce, and when they did appear the owners, recognizing the futility of attempting to make use of them, promptly sent them back to the stables. A humane South street merchant, when his team arrived, had the horses unhitched and took them into his office to escape the severity of the weather."

"A striking exception to the general lack of business was seen in the stores that sold rubber overshoes, Arctics and rubber boots. All day long they were crowded. There were not enough salesmen to wait upon the customers. So great was the rush that many had to wait upon themselves, going to the shelves, picking out what they wanted, taking the article to the cashier's desk and there arranging for their payment and their change."

"A good pair of rubber shoes could be had for 75 cents and a good pair of boots for $2. Naturally, there were higher prices for better goods, but the goods sold at the prices noted would serve for every purpose."

Posted by Frank Roylance at 10:26 PM | | Comments (0)
Categories: Winter weather
        

Could we wake to a surprise?

So what are the chances that we could all wake up to an all-day snow. Or rain? Or nothing?

OK, there's always a chance. This is Maryland meteorology, after all. But I've been on the phone this afternoon with Jeff Warner at Penn State Weather Communications (easier to reach during an "event" that keeps the NWS busy, and better, and more patient explaining this stuff). He's pretty confident we're looking at a little snow, and a bunch of ice tomorrow.

If there is a surprise, he said, it's more likely to be a rainy one. The storm system is too wet to leave us with nothing, and too warm to make an all-out snow very likely.

Anyway, he's expecting an inch or two of snow for Baltimore as the storm moves into the Ohio Valley early tomorrow. If it hasn't started by daybreak, it will be along shortly after that. Then things begin to warm up aloft, and the precipitation begins to melt on the way down. Then it will refreeze as it nears the surface, where the air will remain surprisingly cold given today's highs in the 40s. The forecast high tomorrow at BWI is only 27.

The re-frozen stuff will land as sleet. Ice pellets. But as the warm air layer aloft thickens, and the cold air at the surface thins, the precip falls as rain and freezes on landing. Windshields ice up, road and sidewalks get slick and tree limbs and power lines snap.

The worst of the freezing rain will likely come late in the day and into the night. But as temperatures continue to climb, we could see a changeover to all rain.

That may not last. As the secondary low forms off the Carolina coast, and starts spinning counterclockwise, it will draw arctic air down from our north. And if there's any lingering rain, it may change briefly to snow before it all goes away.

We'll all be a lot smarter by tomorrow morning. For now, here's the NWS forecast if you can get through amid all the snow-panic traffic. And this will get you the watch and advisory info.

Here's AccuWeather's eastern forecast, which much be on a huge server. And here's the satellite loop. And finally, the national radar loop. Very cool. Check out all that moisture streaming in from the Gulf. That's why this will be a wet storm.

Sleep tight. And watch that first step when you go out to get the paper tomorrow.

Posted by Frank Roylance at 6:30 PM | | Comments (0)
Categories: Forecasts
        

A very complex storm

Anyone who thinks weather forecasting for Maryland in winter is easy hasn't been paying attention to this storm. Just take a look at the forecast map in this dispatch from AccuWeather. Cold air from the north, warm air from the south, and just about every precipitation type you can think of sandwiched in between. And that's where millions of us live.

As usual, AccuWeather's chief snow-hawk, Henry Margusity, is arguing that the storm will draw in enough arctic air to give us more snow than the inch or two the Weather Service is forecasting for BWI Accu212 His snow map shows some of us getting 3 to 6 inches. That could happen after the freezing rain tomorrow turns back to snow as the cold air pushes its way in. Click here and watch his video. See if you agree.

But any way you cut it, we're in for some nasty weather here tomorrow. And locations north and west of the I-95 corridor can expect more frozen precipitation, and snow, than the rest of us. My bet is there's no school Tuesday, and maybe Wednesday in the Baltimore area as the slop turns to ice. If they closed for last week's fluff, they'll have to close tomorrow, wouldn't you think? And places well inland, and on up into New England are in for a very memorable storm.

At the same time, we're still sitting here looking at a sunny day, and the warmest temperatures we've seen here on The Sun's weather instruments since Jan. 28. It's 45 degrees out there! But the barometer turned at 9 a.m. and is now sinking fast. Have you taken a look at yours lately?

Posted by Frank Roylance at 1:41 PM | | Comments (6)
Categories: Forecasts
        

Can you say "freezing rain"?

What a mess. What had been shaping up as a good, old-fashioned mid-February snowstorm has morphed into what looks like a sloppy, slippery, snow, sleet, freezing rain and rain event tomorrow for Baltimore and its surrounding counties. The computer models changed their tunes late yesterday afternoon, and the forecast has been getting sloppier ever since.

Here's the official forecast. There is a winter storm watch posted for all of Maryland west of the Chesapeake Bay through Wednesday afternoon. Here's what that looks like.

From all that, and from this morning's discussions at Sterling, here's what they're saying we can expect. Bear in mind that this is still weather; storm tracks can change and so can the details of what you see, when and where.

Look for the precipitation to begin late tonight, most likely after midnight for the Baltimore/DC region. The computer models are slowing the storm down.

It should begin as all-snow for us. The warm air the storm is dragging in from the south isn't expected to get beyond Southern Maryland tonight. By sunrise we could have and inch, maybe two on the ground. Then things get more interesting as the storm forms a secondary low off the Carolina coast, which intensifies.

One piece of the forecast we should bear in mind here is that ground temperatures, and air temperatures near the surface, will likely remain at or below the freezing mark for much of the day Tuesday. So, as the warm air begins to slide farther north atop that cold surface layer, whatever falls will freeze on the way down. It may fall as rain, then freeze en route to the ground, becoming sleet. Ice pellets. Or, it may reach the surface as rain and freeze on contact. That's freezing rain. Windshields, sidewalks, unsalted streets, steps ... everything gets a glaze of ice, and things become very dangerous.

That ice coating also weighs down tree limbs, which weigh down power lines, which snap, which puts lots of us in the dark. Got batteries? Firewood?

Farther south, in Southern Maryland counties, it may change all the way over to rain as surface temperatures rise above freezing. Precisely where the all-rain line forms is anybody's guess.

Beyond this storm, cold, arctic air will return, chasing out the seasonably mild 40s we see today. So most of whatever is on the ground after the storm moves off will likely remain there for the rest of the week.

Posted by Frank Roylance at 11:37 AM | | Comments (0)
Categories: Forecasts
        

February 11, 2007

Storm looking warmer

The latest runs of the National Weather Service's supercomputers are now suggesting this week's storm will take a more northerly track than previously forecast. That means it will draw in more mild air from the south and push the rain/snow line closer to Baltimore.

Prognosticators are now saying there is a stronger chance that, while Baltimore will see snow Tuesday, it may mix with, or turn to freezing rain or rain as the storm progresses. That would hold down snow totals. Here's the afternoon discussion from Sterling.

Here's one of AccuWeather's forecasters on the topic. Here's the latest forecast from the Weather Service, in Sterling, Va.

Meterologist Jeff Warner, at Penn State Weather Communications, told me this afternoon that some mixed precipitation is in the cards for Baltimore.

"I do think you'd go over, probably, to some sleet and actually some rain as well there in Baltimore. Not far to your west, though… farther back into the cold air, there will be quite a bit of snow," he said. He added this storm will produce 10 inches or more in some locations. But probably not for Baltimore.

That said, AccuWeather's snow hawk Henry Margusity is sticking to his snow-guns. Ignore the models, he says.

Posted by Frank Roylance at 2:20 PM | | Comments (6)
Categories: Forecasts
        

"Heavy snow" coming

A "winter storm watch" was posted today for most of Maryland. That means there is a significant potential for heavy snow or ice that could affect travel. Here's how the meteorologists at the Sterling forecast center see it. Here's the official forecast. Notice the reference to "heavy" snow on Tuesday. That means 4 inches or more.

The storm that's threatening us, mostly on Tuesday, is just now coming ashore in California - as rain. But it is expected to shoot across the country in the next day or two and run into arctic air. That cold air has been entrenched here for a week, and is expected to be reinforced on Tuesday with another surge of polar weather.

The storm will begin to draw moisture from the Gulf of Mexico, and sweep it north and east into the mound of frigid air already in place, and make sleet, ice and snow. And once it reaches the Atlantic coast, the storm may well intensify and draw Atlantic moisture in from the northeast. And presto. We get an old-fashioned nor'easter and gobs of snow.

Just how much, of course, is still in debate. As always, it depends on the storm's precise track and speed, and where the rain/mix/snow lines fall. And nobody knows that for sure yet, even though the supercomputers have been cranking on this storm for a week.

Accumap

AccuWeather has us in a zone likely to see up to 6 inches, and there are hints, at least from their snow blogger Henry Margusity, of up to a foot of snow. Here's their take. The Weather Channel is hinting at "several inches" of snow for our area. For Margusity's giddy, worst-case scenario outlook for this storm ("a hum-dinger") click here and watch his video.

Here's a bit of the discussion this morning from Sterling (edited by me for clarity), where they are beginning to hint at 5 inches or more:

"CENTRAL VIRGINIA AND
LOWER SOUTHERN MARYLAND STILL MAY EXPERIENCE SOME MIXING (FREEZING
RAIN AND SLEET). (ONE COMPUTER MODEL) EVEN BRINGS SOME SLEET INTO DC/BWI.
THIS MAY BE THE CASE...BUT WILL NOT EXPAND MIXED PRECIP THAT FAR
NORTHWEST AT THE MOMENT. EVEN WITH MIXING THOUGH...OUR ENTIRE CWA (FORECAST AREA) HAS THE
POTENTIAL TO RECEIVE APPRECIABLE SNOWFALL ACCUMULATIONS THAT WOULD
REACH WARNING CRITERIA FROM THIS HIGH QPF (WET) STORM WITH HIGH IMPACT
POTENTIAL.

THEREFORE...WILL BE ISSUING A WINTER STORM WATCH FOR OUR
ENTIRE CWA FOR SNOW...WITH THE POSSIBILITY OF MIXED PRECIPITATION AS
WELL OVER THE POTOMAC HIGHLANDS...CENTRAL VIRGINIA AND LOWER
SOUTHERN MARYLAND. WHILE SOME WINTRY PRECIPITATION WILL OCCUR
THROUGH MONDAY NIGHT...THE WATCH WILL COVER A 24 HOUR PERIOD FROM
TUESDAY MORNING THROUGH WEDNESDAY MORNING WHEN THE WARNING CALIBER
HIGH IMPACT WINTER CRITERIA ARE EXPECTED (5 INCHES OF SNOW/SLEET IN
A 12 HOUR PERIOD AND/OR GLAZE OF ICE 1/4 INCH OR GREATER IN A 12
HOUR PERIOD).

(COMPUTER CONSENSUS) INDICATE A SLIGHTLY SLOWER EXIT WITH THE STORM AS
WELL...AND HAVE INCREASED POPS (PRECIPITATION PROBABILITIES) ON WEDNESDAY FOR LINGERING SNOW.
BEYOND WEDNESDAY...COLD NORTHWEST FLOW DEVELOPS AS SURFACE HIGH
PRESSURE DROPS INTO THE DEEP SOUTH OVER THE WEEKEND. WINDS WILL BE
GUSTY THROUGH MUCH OF THE PERIOD...AND TRAJECTORIES WILL BE
FAVORABLE FOR UPSLOPE SNOW SHOWERS OVER OUR WESTERN ZONES.
TEMPERATURES WILL BE BELOW CLIMATOLOGY (SEASONAL NORMS)  DUE TO THE COLD AIR MASS. IF
THERE IS A SNOWPACK...TEMPERATURES WILL NEED TO BE DROPPED EVEN MORE
DUE TO ALBEDO-PRODUCED RADIATIVE EFFECTS (WHITE SNOW COVER REFLECTS MORE SOLAR HEAT).

So, buckle up Baltimore. Something white this way comes.

Posted by Frank Roylance at 10:09 AM | | Comments (1)
Categories: Winter weather
        

February 10, 2007

A few inches? A foot?

The guesses are still all over the map as to just how much snow we'll get out of this storm. What does seem apparent is that we will get a brief return to normal February temperatures (low 40s) Monday, followed by, perhaps, some rain, then falling temperatures overnight Monday into Tuesday with rain changing to snow overnight, then snow for Tuesday into Wednesday, and maybe longer.

Just how much we get depends on whose computer models you want to believe, and which track the storm finally decides to take.

Here is the National Weather Service forecast for Baltimore. They have posted a Hazardous Weather Outlook statement. Here's a bit of their discussion late Saturday (edited by me for clarity):

"(COMPUTER GUIDANCE) SUGGESTS THAT BOUNDARY LAYER TEMPS COULD BE
WARM ENOUGH FOR RAIN EAST OF MOUNTAINS LATE MONDAY...CHANGING TO SNOW OVERNIGHT. SUSPECT
EFFECTS OF COLD AIR DAMMING NOT BEING CONSIDERING IN GUIDANCE SOLUTIONS. (MEANING THE COMPUTERS MAY NOT BE TAKING THE ENTRENCHED COLD AIR INTO ACCOUNT IN THEIR TEMPERATURE FORECASTS)

AS MAIN SYSTEM APPROACHES TUES ...THIS GUIDANCE CYCLE... SUGGESTS THAT CHANCE FOR MIXED PRECIPITATION SPREADS AS FAR NORTH AS
(WASHINGTON) TUES. (COMPUTER MODEL) THEN POINTS TO A LOCATION NEAR
MASON- DIXON LINE FOR BEST BANDED (HEAVY) PRECIPITATION TUES AFTERNOON...

(STORM) SYSTEM HAS POTENTIAL TO PAINT SOME GOOD SNOW
TOTALS...BUT IT'S STILL TO BE DETERMINED EXACTLY WHERE THAT WILL BE. WE NEED ANOTHER
(COMPUTER) RUN /OR TWO/ ... BEFORE HEADLINES CAN BE RAISED."

And here's AccuWeather's take. One of their bloggers is guessing a foot of snow for Baltimore and Washington. But I wouldn't take that to the bank. Yet.

Posted by Frank Roylance at 10:50 PM | | Comments (1)
Categories: Winter weather
        

Get a load of Saturn

Saturn, the 6th planet from the sun and the only one recognizable by its profile alone, is at opposition tonight (Feb. 10). That means the ringed gas giant is at its closest approach to the Earth of the year (currently about 762 million miles away), rising in the east as the sun sets in the west.

It's easily visible to the naked eye. Looking just a bit north of due east, at about 6:30 p.m., on any clear night this month, it is the brightest "star" near the eastern horizon after sunset. Don't confuse it with the brighter winter stars, such as Sirius (the "dog star") and Procyon, which gleam a bit higher and much brighter in the sky. At midnight Saturn stands high overhead, just south of straight up. Some observers see a pale yellowish cast to its light.

Guy Ottewell's Astronomical Calendar notes that Saturn is currently shining at a magnitude of about zero (the lower the number, the brighter the object), which is as bright as it will be to the naked eye for decades to come. Part of the reason is that its rings, as seen from Earth's perspective, are tilting closer and closer each year to edge-on. At that point they reflect almost no sunlight our way at all, dimming the entire planet's light as seen from Earth.

Those rings are currently tilted at about 15 degrees from our perspective. And they're well worth seeing. You'll need to find a telescope, but I guarantee you your first view of the ringed planet will be an experience you will never forget. Find one of Baltimore's streetcorner astronomers, or attend one of the open houses at area observatories, including the Maryland Science Center. Take the kids.

For a closer look at Saturn, visit the Cassini mission website. Cassini is still orbiting Saturn, sending back amazing images of the planet, its wafer-thin rings and its many moons.

Posted by Frank Roylance at 9:00 AM | | Comments (0)
Categories: Sky Watching
        

February 9, 2007

Latest on next week's snow

UPDATE 4 P.M. FRIDAY: Forecasters this afternoon posted the following Hazardous Weather Advisory:

"A STORM COMING OUT OF THE SOUTHERN PLAINS AND DEVELOPING OFF THE
SOUTHEAST COAST OF THE UNITED STATES WILL LIKELY AFFECT THE
REGION EARLY NEXT WEEK. SNOW MAY BEGIN AS EARLY AS MONDAY...
CONTINUING THROUGH TUESDAY NIGHT. AT THIS POINT TUESDAY LOOKS TO
HAVE THE BEST POTENTIAL FOR HEAVY SNOW AS THE STORM INTENSIFIES
OFF THE COAST. THIS SYSTEM WILL NEED TO BE CLOSELY MONITORED
THROUGH THE WEEKEND FOR THE POSSIBILITY OF A SIGNIFICANT STORM
EARLY NEXT WEEK. ALTHOUGH IT IS TOO EARLY TO FORECAST SPECIFIC
SNOWFALL ACCUMULATIONS...STAY ALERT THROUGH THE WEEKEND FOR THE
LATEST ON THIS POTENTIAL WINTER EVENT.

AFTER THE STORM...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED
TUESDAY AND WEDNESDAY FOR THE TIDAL POTOMAC AND MARYLAND PORTION
OF THE CHESAPEAKE BAY.

VERY COLD TEMPERATURES AND WIND CHILLS SHOULD BE EXPECTED TUESDAY
NIGHT THROUGH THURSDAY MORNING."

EARLIER: Forecasters at the National Weather Service office in Sterling seem to be getting more comfortable with their predictions for the storm headed this way next week. The computer models are beginning to converge on a solution, and the probabilities have climbed from 60 to 70 percent this afternoon. Here's the forecast from Sterling. Way too early for them to venture accumulation predictions.

And here's a bit of this morning's discussion (edited by me for clarity):

"QUIET CONDITIONS EXPECTED THRU THE WEEKEND AS HIGH PRESSURE BUILDS OVER THE
AREA. ATTENTION THEN TURNS TO SIGNIFICANT WINTER STORM WHICH APPEARS LIKELY
TO IMPACT THE REGION MON NIGHT-TUE. LOW PRESSURE (STORM) FORECAST TO ORGANIZE OVER
THE SOUTHERN PLAINS ON SUNDAY AND MOVE EAST ACROSS THE NORTHERN GULF COAST STATES
AND ACROSS THE CAROLINAS TUESDAY.

"FINALLY...BEGINNING TO SEE SOME CONSISTENCY IN THE MODELS WITH RESPECT TO TRACK OF (STORM) ... AND
AN ENSEMBLE (COMPUTER) PLOT ALSO SHOWS MUCH BETTER CLUSTERING THAN YESTERDAY
INCREASING CONFIDENCE THAT WE'LL SEE A HEAVY SNOW EVENT SOMEWHERE
ACROSS OUR (FORECAST AREA). BASED ON (COMPUTER MODEL CONSENSUS) ... STILL THINK MIXED PRECIP IS A GOOD POSSIBILITY
ACROSS OUR SOUTHERNMOST COUNTIES FROM NELSON/ALBERMARLE EAST THRU ST
MARYS COUNTY. COLDER WEATHER RETURNS FROM WEDNESDAY THRU THE END OF THE WEEK.
MODELS HAVE BACKED OFF ON SECOND STORM THAT THEY WERE ADVERTISING
COUPLE OF DAYS AGO."

Lest you get too freaked out, in weather parlance, "heavy snow" means 4 inches or more.

AccuWeather, of course, is much more enthusiastic about the stormy prospects for next week. Here's snow-hawk Henry Margusity on the Tuesday storm, which he calls a "Virginia, Maryland Special," with 6 inches of accumulation or better, and Baltimore, Washington, Ocean City getting "the good snows." Watch the video.

Finally, here's a 31-day loop of snow cover across North America. Slow it down and you can watch the snow line creeping up on Baltimore as January turns to February. By this time next week, we'll finally be well into the white zone.

In the meantime, we're headed into a nice, sunny-but-cold weekend. Cold for this time of year, that is. If the forecast holds up, and the high reaches 36 degrees at BWI tomorrow, it will be the first time we've topped the freezing mark since last Saturday at 9 p.m., when it was 33.5 degrees here at The Sun.

Posted by Frank Roylance at 10:47 AM | | Comments (1)
Categories: Forecasts
        

Ridiculous snow

AccuWeather has posted a small gallery of photos from upstate New York, where persistent lake-effect snows have buried a swath of countrside downwind of Lake Ontario. It's worth a look. Maybe it will get you in the mood for next week's snow here! Ha!  Click here.

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

February 8, 2007

Six inches? A foot? Snow hysteria builds

AccuWeather continues to hype the potential for heavy snow as the continent's weather systems rearrange themselves next week. One of their bloggers is discussing several scenarios, a couple of which could bring us heavy snow, and one of which could bring a foot or more. We could even see a series of snowstorms in the coming weeks. Here's his menu of winter weather possibilities.

The National Weather Service, meanwhile, is being more cautious. Their discussion supports the likelihood of "cold air damming," which means stubborn cold air in our region, coupled with the approaching precipitation Monday night and Tuesday, producing "THE POTENTIAL
FOR A HEAVY SNOWFALL SOMEWHERE ACROSS THE REGION."

It is beginning to seem inevitable that, with this changing pattern, we will have cold air in place in the Mid-Atlantic and Northeast next week, and a new pattern of successive storms slogging across the continent. That seems quite likely to be the prescription for something wet, probably white, perhaps deep, and maybe just the beginning of a snowier pattern in our lives.

Posted by Frank Roylance at 4:08 PM | | Comments (0)
Categories: Forecasts
        

Snowstorm early next week?

The National Weather Service continues to watch computer models suggesting a "significant" winter storm for our region next Monday or Tuesday as a milder,stormier pattern begins to set up to oust this cold, dry, arctic air.

The models seem to be pushing the snow/mixed-precip line farther north, so that Southern Maryland may see a mixture of precipitation types. But the metro areas would seem to be above the snow line - at least as far as these long-range guesstimates are concerned. Anyway, here's the morning discussion from Sterling:

"OP MODELS AND ENSEMBLE GUIDANCE CONTINUE TO INDICATE THE POTENTIAL
FOR A SIGNIFICANT WINTER STORM TO IMPACT THE REGION MOST LIKELY DURING THE
MON NIGHT-TUE TIME FRAME ALTHOUGH SIGNIFICANT DIFFERENCES ARE STILL NOTED
WITH RESPECT TO THE TRACK OF THIS SYSTEM. HOWEVER...TREND IN THE
MODELS, ESPECIALLY ECMWF, IS FOR A TRACK FURTHER TO THE NORTH WHICH
INCREASES THE POTENTIAL FOR MIXED PRECIP FOR OUR SOUTHERN-MOST COUNTIES.
HAVE INTRODUCED GENERIC RAIN/SNOW WORDING TO SOUTHERN COUNTIES FROM
HIGHLAND COUNTY EAST THRU CHO/EZF AND ST MARYS COUNTY FOR THE THREAT
OF MIXED PRECIP. WEEKEND LOOKS RELATIVELY WARM WITH TEMPS GETTING
INTO THE MID AND UPPER 30S."

AccuWeather, as usual, has taken the outer position on this particular limb. One of their bloggers is already talking about as much as 6 inches in our region. Obviously, a lot can happen between now and Monday. But these outbreaks of deep, arctic cold are very often ended with big snowfalls when the sub-tropical jet begins to push back, bringing warmer, wetter air into play, and into collision with the entrenched cold air. Wet and cold spell snow somewhere.

For now, here's the forecast. Blue skies and sunshine will moderate temperatures around here somewhat. But we're still 8 or 10 degrees below normal for this time of year at BWI. Starry nights, too. Orion, Taurus the Bull, Sirius, Procyon, Saturn, even Venus and Mercury have been glorious. Enjoy these naked-eye wonders, because it's way too cold to be out there with a telescope.

Posted by Frank Roylance at 8:27 AM | | Comments (0)
Categories: Forecasts
        

February 7, 2007

Lighting! Fireworks! Comet!

Australians who turned out recently for a fireworks display on a beach in Perth were treated to a multi-media show they may never have expected. Comet McNaught appeared through the clouds on the far horizon, and a spectacular burst of lightning provided a striking addition to the display. Click here.

Posted by Frank Roylance at 4:26 PM | | Comments (2)
Categories: Cool pictures
        

Read IPCC global warming report

You read the news stories, and watched the TV sound bites. If you're really interested in the latest scientific consensus on global climate change, you'll want to download and read the full Summary for Policy Makers from the 4th Assessment Report from the Intergovernmental Panel on Climate Change (IPCC). There is also a link to the Webcast from the news conference held when the report was released. Click here.

Posted by Frank Roylance at 4:11 PM | | Comments (0)
Categories: Notes to readers
        

Broom snow, more cold

Swept the walks and cleared off the cars this morning with a broom. Ten minutes. Done. Clear roads. And a snow day to boot. That's the kind of snow we (or at least some of us) like to see.

Here's the snowfall map for the overnight event.

I never saw a flake in the air. The stars were shining when I got home from work, and the snow had already ended by the time I looked outside again at 4:30 a.m. The instruments at BWI-Marshall recorded light snow from about 11 p.m. until the 7 a.m. report.

And there's nothing more in the wings that looks like snow. Just sunshine and cold temperatures. The forecast calls for temperatures to continue about 10 degrees below normal. Highs in the 30s, lows in the teens. That beats 20 degrees below the long-term averages, but it's still quite cold for this time of year.

Forecasters are keeping watch, however, on the possibility of a bigger snowfall next week. Here's part of this morning's discussion:

"(COMPUTER MODELS) CONTINUE TO INDICATE THE POTENTIAL FOR A MORE SIGFNIFICANT 
WINTER STORM IMPACTING THE REGION AROUND VALENTINES DAY. WILL BE
WATCHING THIS ONE VERY CLOSELY OVER THE WEEKEND."

Moonsnow

One hardy reader has sent in a pack of snow photos already this morning. Have a look, then send in your own. I'm sure we can do better.

Posted by Frank Roylance at 9:49 AM | | Comments (0)
Categories: Winter weather
        

February 6, 2007

An inch or two of fluff

The National Weather Service has issued a snow advisory for our area, calling for 1 to 2 inches of dry snow here as this Alberta Clipper blows by tonight. Here's the lowdown:

"THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A
SNOW ADVISORY...WHICH IS IN EFFECT FROM 7 PM THIS EVENING TO 7 AM
EST WEDNESDAY.

LIGHT SNOW WILL MOVE INTO THE AREA WITHIN A FEW HOURS OF 9 PM
THIS EVENING. ONE TO TWO INCHES ARE EXPECTED FOR ALL OF THE REGION
SOUTH AND WEST OF BALTIMORE CITY... INCLUDING BALTIMORE CITY AND THE
WASHINGTON METRO AREA. FURTHEST TO THE SOUTHWEST... AROUND
CHARLOTTESVILLE... STAUNTON... AND HARRISONBURG... 3 TO 5 INCHES
OF SNOW ARE EXPECTED. SNOW WILL EXIT THE REGION AROUND 6 AM. DUE
TO THE COLD CONDITIONS...THIS WILL BE A LIGHT AND RELATIVELY DRY
SNOW.

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE PRIMARILY
TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND
LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING."

Posted by Frank Roylance at 1:40 PM | | Comments (0)
Categories: Winter weather
        

Coldest morning in three years

The thermometer out at BWI-Marshall sank to 8 degrees just before 5 a.m. today. That's the coldest reading there since Feb. 1, 2004. Here are some other lows this morning from across the region:

The WeatherDeck in Cockeysville:  7 degrees

The Sun, Calvert & Centre: 10 degrees

Inner Harbor:  12 degrees

Martin State Airport:  12 degrees

Aberdeen Proving Ground:  9 degrees

Frederick Airport:  7 degrees

Hagerstown:  3 degrees

Reagan Nat'l Aiport:  10 degrees

Dulles Airport:  6 degrees

York Pa. Airport:  4 degrees

State College, Pa.:  0 degrees

The last time Baltimore saw a stretch of bitter cold like this was in January and February 2004. It was 6 degrees on Jan. 10 of that year, and 7 degrees the next morning. The mercury dipped to 8 again on the 25th, and to 8 degrees on Feb. 1.

And how about these barometer readings? The Sun's instrument reached 30.43 inches overnight. That's pretty high pressure, consistent with this very cold, dry, dense mass of arctic air that's moved in. (Although it's not much compared with the highest ever recorded in the U.S.: 31.85 inches, in Northway, Alaska in January 1989.) Check your low temperatures and barometer readings and leave us a comment.

Forecasters today are still anticipating a little snow early tomorrow morning as that Alberta Clipper - a weak disturbance out of the Canadian Plains - comes barreling through. They're talking about maybe an inch, although higher accumulations are possible in some spots. Here's AccuWeather on the topic.

The real issue is that the roads are very cold, and will support snow accumulations. Salt may have only limited effect. So we may see some slippery conditions and maybe a school delay in the morning.

Meanwhile, the chatter from Sterling is pretty interesting. Here's part of it, (edited by me for clarity):

"THROW ANOTHER LOG ON THE FIRE..." COLDEST NIGHT I CAN RECALL IN QUITE
A WHILE HERE...ALONG W/ SOME VERY HIGH PRESS READINGS ... TEMPS NEARLY 20 DEG BELOW CLIMATOLOGICAL NORMS.
BRILLIANT SUNSHINE DURING MORNING HRS. HIGH CLOUDS FILTER IN DURING AFTERNOON TO
ANNOUNCE THE ARRIVAL OF A SHORT WAVE ROCKETING OUT OF THE UPPER
MIDWEST ...

THAT SYSTEM WILL BRING SNOW TO THE REGION TONIGHT. PRECIPITATION-TYPE IS CERTAINLY NOT AN ISSUE...AND W/ SO MUCH DRY AIR IN PLACE THIS WILL BE A VERY POWDERY
SNOW. BUT JUST AS IT WILL ENTER THE AREA RAPIDLY, SO WILL IT EXIT. TIME
WILL BE A LIMITING FACTOR ON SNOW AMOUNTS. THINK HIGHEST AMOUNTS FOR OUR (FORECAST AREA) WILL BE JUST NORTH OF THE TRACK..ACROSS CENTRAL VA. THINK HIGHLAND/
PENDLETON AREA COULD SEE 2-4"...AN INCH OR TWO IN THE DC METRO
AREA...LESS THAN AN INCH NORTH OF BALTIMORE.

MAINLY COLD AND TRANQUIL CONDITIONS ARE EXPECTED THROUGH MUCH OF THIS
PERIOD AS AN AREA OF HIGH PRESSURE GRADUALLY BUILDS SOUTHEASTWARD FROM NORTHWEST
CANADA. ENSEMBLE (COMPUTER MODEL) GUIDANCE INDICATES A SLIGHT MODERATION TO THE COLD WEATHER NEXT WEEK AS FLOW BECOMES MORE ZONAL. BY NEXT TUESDAY SPAGHETTI
PLOT SHOWS AN AREA OF STORMINESS ACROSS THE MID SOUTH WITH HIGH PRESSURE
SOUTH OF JAMES BAY NOSING DOWN ALONG THE SPINE OF THE APPALACHIANS.
STILL A WEEK AWAY TO MONITOR THIS POTENTIALLY SIGNIFICANT PRECIPITATION MAKER." 

Posted by Frank Roylance at 10:29 AM | | Comments (3)
Categories: Winter weather
        

February 5, 2007

After the snow, Venus and Mercury

It's too late for tonight, and Tuesday night we'll likely have clouds in advance of the snow. But Wednesday and Thursday nights may be good opportunities for backyard stargazers to catch a glimpse of Venus and Mercury.

Venus is brilliant in the western sky right after sunset these days. No one under clear skies could possibly miss it. It's currently the brightest object in the western sky. Venus is about 140 million miles from Earth at present.

Mercury is smaller, dimmer and harder to spot, but this week the nearest planet to the sun will be about as far east of the setting sun as it gets. So with clear skies, it should be a fairly easy naked-eye object. Mercury is presently about 93 million miles from Earth.

Look for Mercury after sunset, to the right and below Venus. Here's a shot taken by Ante Pavlovic, from Zagreb, Croatia.

Mercury

It will look like a small, steady star. Here's a finder map from Spaceweather.com  And here are some links to pictures that astrophotographers have been shooting in recent days. Good luck.

Posted by Frank Roylance at 6:42 PM | | Comments (2)
Categories: Sky Watching
        

Frigid, then snow

The mercury sank to 11 degrees at BWI this morning, and the forecast for the overnight low tonight is a mere 7 degrees. And if that's not wintry enough for you, the folks out at Sterling are saying that there's an Alberta Clipper headed our way overnight Tuesday into Wednesday that could drop an inch or two of snow on the roads by rush hour Wednesday morning. Or maybe more if we get lucky. Here's a snippet from this morning's discussion at Sterling:

"WILL HAVE TO MONITOR THIS
SYSTEM CLOSELY AS PREDICTING SNOW AMOUNTS WITH CLIPPER SYSTEMS CAN
SOMETIMES BE VERY CHALLENGING. ALTHOUGH AMOUNTS ARE EXPECTED ON THE
LIGHT SIDE IT COULD CAUSE BIG IMPACTS ON HIGHWAYS AS TEMPERATURES
WILL BE VERY COLD (ONLY ABOUT 20F) AND SNOW WILL BE JUST IN TIME FOR
THE WED MORNING RUSH HOUR."

Are we having fun yet?

This morning's low of 11 degrees, as bracing as it was, wasn't close to the record of minus-1 degree F. for the date, set in 1996. Tomorrow's record is plus-1 degree, set in 1895. We won't touch that one either at BWI. Anybody get colder readings than BWI? It was 11 on the WeatherDeck in Cockeysville, and 10 on the car thermometer.

Still not wintry enough for you? Go visit my mother-in-law in Erie, Pa., where the lake-effect snow is still piling up. Erie International Airport is snowy, but open.

Posted by Frank Roylance at 10:44 AM | | Comments (7)
Categories: Winter weather
        

February 4, 2007

Arctic cold tonight, tomorrow

Hit the indoor malls today, not the outdoor variety. Make it a quick walk for Fido tonight, not a leisurely stroll. The mercury is headed lower, and the wind speeds will be picking up. So wind chills will be bumping along in the single digits, or worse. Here's AccuWeather's take on the arctic invasion - the coldest of the season.

The National Weather Service has issued a wind chill advisory for western Maryland and the counties along the Pennsylvania border:

"BITTERLY COLD TEMPERATURES AND LOW WIND CHILL VALUES WILL CONTINUE
TO AFFECT THE REGION THROUGH THE EARLY WORK WEEK. MONDAY NIGHT MAY
BE THE COLDEST NIGHT OF THIS STRETCH...EVEN COLDER THAN TONIGHT
WILL BE.

A WIND CHILL ADVISORY MEANS THAT VERY COLD AIR AND STRONG WINDS
WILL COMBINE TO GENERATE LOW WIND CHILLS. THIS WILL RESULT IN
FROST BITE AND LEAD TO HYPOTHERMIA IF PRECAUTIONS ARE NOT TAKEN.
IF YOU MUST VENTURE OUTDOORS...MAKE SURE YOU WEAR A HAT AND
GLOVES...COVERING ALL EXPOSED SKIN."

Living in the Hereford Zone? Check out the lows for this week. Just be happy you're not in Cumberland, where lake effect snows will be a factor most of the week. Or in Erie, Pa., where my mother-in-law woke up to this forecast today.

Posted by Frank Roylance at 10:33 AM | | Comments (0)
Categories: Winter weather
        

February 2, 2007

Our dry winter, from space

In addition to the lack of snow, Baltimore saw a quite a bit less rain than normal in December and January - about 2.5 inches short of the 30-year average.

That, it turns out, is consistent with the pattern that typically emerges during an El Nino event, the periodic, abnormal warming of surface waters in the central and eastern tropical Pacific Ocean. Using its Earth-observing satellites, NOAA has documented the scarce precipitation in the East, as well as surpluses in other parts of the country as a consequence, in part, of the El Nino event, which is now waning. To see, and read, more, click here.

Rain_1 On the map, yellow corresponds with dry weather, green with wet.

Posted by Frank Roylance at 2:20 PM | | Comments (0)
Categories: Cool pictures
        

Winter weather wimps out

Another pathetic display by Old Man Winter. All that fuss and we get a trace of snow at BWI. We're showing one hundredth of an inch of precip here at The Sun's weather station. We haven't even topped ONE INCH yet for the season at the airport. Snow in Mexico last month, in North Carolina and New Jersey, but nothing here. Here's the laughable report from Sterling on yesterday's "accumulations."

Now that the IPCC's fourth report on global warming science is out, maybe those Marylanders who love snow and all the commotion around here when we get a real snowstorm should read up and find a new place to live - in Oswego, N.Y., or Chibougamau (look it up).

Of course, by Tuesday folks will be saying, "Global warming? What global warming? It's 8 degrees outside my house this morning! Get me more fossil fuel!"  Meanwhile, it's 45 degrees - ABOVE zero - today in Anchorage.

Here's the official forecast from Sterling for the weekend and on into next week. After tomorrow, we won't see the melty side of freezing until a week from now, if then. So forget the new 40-inch plasma TV for the Super Bowl. You're going to need that money for the February heating bill.

But as for snow, there is, for now, nothing at all of substance in the wings. The cold weather that's coming is a start. But we'll need a nice, wet, low-pressure system to crank up somewhere in the Gulf region, and a storm track that can carry it up the coast. Until then, we got bupkis. (Look it up.)

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

February 1, 2007

Snow advisory cancelled

Not cold enough, and not enough moisture. The National Weather Service has cancelled the "winter weather advisory" that had been posted all day for our area. What little snow we might have gotten from this pathetic little kerfuffle has pretty much disappeared. Here's all that's left in Sterling's quiver:

"SOME ISOLATED LIGHT MIXED PRECIPITATION IS EXPECTED
OVERNIGHT...ESPECIALLY SOUTH OF A LINE FROM BALTIMORE TO
CHARLOTTESVILLE. NO ACCUMULATION IS EXPECTED. ISOLATED SLICK SPOTS
COULD DEVELOP ON LIGHTLY TRAVELLED SECONDARY ROADS. PRECIPITATION
WILL FALL AS RAIN OVER LOWER SOUTHERN MARYLAND."

Better luck next time, kids.

Posted by Frank Roylance at 9:16 PM | | Comments (3)
Categories: Winter weather
        

Warmest January since ...

For those who missed today's dead-tree editions, here's how our Weather Page recapped January's weather:

Some January, huh? Less than an inch of measurable snow; seven days with highs at BWI of 60 or higher, and nine that never sank below freezing. The average temperature for the month was about 39, nearly 7 degrees above normal. The last time we had a January this mild and snowless? Well, you'd have to go all the way back to ... er, last year. January 2006 saw only a trace amount of snow, and temperatures averaged 41.6 degrees. Welcome to Savannah by the Bay.

The Weather Page comments are also available online, from the www.marylandweather.com main page. Look below the blog posts.

We'll soon be wishing for mild temperatures. And February may yet generate some real snow. I've been asked how often Baltimore gets a December and January as snow-free as the months just past. Here's a rundown of some disappointing snowfall stats, in inches, for December and January at BWI:

2006-2007:   December, Trace  January, 0.9

1997-1998:   December, 0.4  January, 0.7

1994-1995:   December, 0.0  January. 0.3

1972-1973:   December, Trace  January, Trace

1968-1969:   December, Trace  January, 0.1

1949-1950:   December, Trace  January, 0.5

Posted by Frank Roylance at 1:55 PM | | Comments (2)
Categories: By the numbers
        

A winter mess

Here's the 4 p.m. update. Even less impressive than this morning's predictions. Sleep easy.

EARLIER: Can't get to the National Weather Service web site because of the heavy traffic? Here's the full "winter weather advisory" for the Baltimore region.

"THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A
WINTER WEATHER ADVISORY...WHICH IS IN EFFECT FROM 9 AM THIS
MORNING TO 9 AM EST FRIDAY.

TWO WEAK AREAS OF LOW PRESSURE WILL COMBINE TO BRING TWO PERIODS
OF WINTER WEATHER BETWEEN THIS MORNING AND FRIDAY MORNING.

FIRST... THE INITIAL EVENT WILL BE A WEAK STORM PASSING TO OUR SOUTH
TODAY. THIS FIRST STORM WILL MAINLY AFFECT WEST CENTRAL VIRGINIA...
CENTRAL VIRGINIA... AND LOWER SOUTHERN MARYLAND. THOSE AREAS WILL
LIKELY SEE AROUND AN INCH OF SNOW TODAY... STARTING DURING THE MID
MORNING IN WEST CENTRAL VIRGINIA... AND EARLY THIS AFTERNOON IN
LOWER SOUTHERN MARYLAND.

FOR THE REST OF THE REGION TODAY... INCLUDING CENTRAL AND WESTERN
MARYLAND... NORTHERN AND NORTHWESTERN VIRGINIA... EASTERN WEST
VIRGINIA... AND THE BALTIMORE AND WASHINGTON METRO AREAS... WE HAVE
A HAVE A CHANCE OF SEEING SOME SNOW SHOWERS AFTER MID MORNING. ANY
ACCUMULATION IS EXPECTED TO BE LESS THAN AN INCH DURING THE DAY
TODAY.

SECOND... THERE IS ANOTHER WAVE WITH THIS EVENT. A SECOND STORM
PASSING TO OUR SOUTH IS EXPECTED TO STRENGTHEN OFF THE COAST AND
BRING SOME HEAVIER PRECIPITATION TO THE AREA AFTER 10 PM TONIGHT
INTO FRIDAY MORNING. HOWEVER... WITH THE STORM TONIGHT... WARMER
TEMPERATURES WILL HAVE MOVED INTO THE LOWER ATMOSPHERE. THIS WILL
CAUSE THE PRECIPITATION TO FALL AS SNOW IN THE MOUNTAINS...BUT A
MIX OF SNOW...FREEZING RAIN... AND RAIN ACROSS MOST OF THE REGION.
PRECIPITATION WILL END ACROSS THE REGION BY MID MORNING FRIDAY.

FOR THE SHENANDOAH VALLEY AND AREAS WEST OF WASHINGTON AND
BALTIMORE... THE SECOND WAVE OF SNOW IS EXPECTED TO DEVELOP DURING
THE LATE EVENING AND THEN MIX WITH OR CHANGE TO RAIN AND FREEZING
RAIN. EXPECT ONE TO THREE INCHES OF ACCUMULATION AND THEN SOME ICING
ON TOP DURING THE NIGHT TONIGHT.

FOR WASHINGTON AND BALTIMORE AND FREDERICKSBURG... EXPECT SNOW TO
DEVELOP IN THE LATE EVENING AND THEN MIX WITH OR CHANGE TO RAIN AND
FREEZING RAIN. EXPECT ONE OR TWO INCHES OF ACCUMULATION AND THEN
SOME ICING ON TOP DURING THE NIGHT TONIGHT.

FOR SOUTHERN MARYLAND SNOW WILL LIKELY CHANGE TO RAIN AND FREEZING
RAIN TONIGHT. UP TO AN INCH OF ACCUMULATION WITH SOME LIGHT ICING IS
POSSIBLE.

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...OR
FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING."

Still got your fingers crossed for a big surprise from this snowstorm? Don't hold your breath.

Posted by Frank Roylance at 8:13 AM | | Comments (1)
Categories: Winter weather
        
Keep reading
Recent entries
Archives
Categories
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
-- ADVERTISEMENT --

Sign up for FREE weather alerts*
Get free Baltimore Sun mobile alerts
Sign up for weather text alerts
SKY NOTES WEATHER

Returning user? Update preferences.
Sign up for more Sun text alerts
*Standard message and data rates apply. Click here for Frequently Asked Questions.
Maryland Weather Center


Area Weather Stations
Resources and Sun coverage
• Weather news

• Readers' photos

• Data from the The Sun's weather station

• 2011 stargazers' calendar

• Become a backyard astronomer in five simple steps

• Baltimore Weather Archive
Daily airport weather data for Baltimore from 1948 to today

• National Weather Service:
Sterling Forecast Office

• Capital Weather Gang:
Washington Post weather blog

• CoCoRaHS:
Community Collaborative Rain, Hail and Snow Network. Local observations by volunteers

• Weather Bug:
Webcams across the state

• National Data Buoy Center:
Weather and ocean data from bay and ocean buoys

• U.S. Drought Monitor:
Weekly maps of drought conditions in the U.S.

• USGS Earthquake Hazards Program:
Real-time data on earthquakes

• Water data:
From the USGS, Maryland

• National Hurricane Center

• Air Now:
Government site for air quality information

• NWS Climate Prediction Center:
Long-term and seasonal forecasts

• U.S. Climate at a Glance:
NOAA interactive site for past climate data, national, state and city

• Clear Sky Clock:
Clear sky alerts for stargazers

• NASA TV:
Watch NASA TV

• Hubblesite:
Home page for Hubble Space Telescope

• Heavens Above:
Everything for the backyard stargazer, tailored to your location

• NASA Eclipse Home Page:
Centuries of eclipse predictions

• Cruise Critic: Hurricane Zone:
Check to see how hurricanes may affect your cruise schedule

• Warming World:
NASA explains the science of climate change with articles, videos, “data visualizations,” and space-based imagery.

• What on Earth:
NASA blog on current research at the space agency.
Most Recent Comments
Blog updates
Recent updates to baltimoresun.com news blogs
 Subscribe to this feed
Charm City Current
Stay connected