The WeatherBlogger would like to wish all our faithful readers, and anyone else who stumbles across this site during the next week, a very happy holiday season. I will be taking a break with my family, but I'll be back in the saddle Jan. 3. Thanks for your interest and kind comments. The numbers have really been amazing. Be safe, stay warm and we'll see you all back here "next year."

Frank Roylance

P.S.: Look for the annual Stargazers' Calendar for 2006 in the Health and Science section of The Sun on FRiday, Dec. 30.

Posted by Frank Roylance at 5:43 PM | Permalink | Comments (1)
Categories: Notes to readers
        

The National Hurricane Center has concluded that Hurricane Katrina struck the Gulf Coast in August as a Category 3 storm, not a Category 4, as was reported at the time. A more thorough review of the available data indicates the storm's top sustained winds at landfall had fallen below the 131-mph lower threshold for Category 4 storms, as set by the Saffir-Simpson Scale of Hurricane Intensity.

The revision could have an impact on the conclusions of engineers who are studying the failure of New Orleans' levee system. Those dikes were supposedly designed to withstand a Category 3 storm, but not necessarily a Cat. 4.

To read the full NHC Katrina assessment, click here, then scroll down to "Katrina" and click on the file format of your choice.

Posted by Frank Roylance at 11:36 AM | Permalink | Comments (0)
Categories: Hurricane background
        

If you're headed for the Deep South for the holiday, you're in luck. High pressure over the region is providing lots of sunshine and boosting temperatures into the 50s and 60s for the next several days.

If you're staying in Central Maryland, it means you'll enjoy a flow of warm southerly, or southwesterly breezes off that high. That will scrub any hopes for a white Christmas, of course. Temperatures are expected to creep into the 40s and 50s here over the weekend.

But the cold air will return. It's still late December, after all. Look for highs only in the 30s by Tuesday, and the 20s on Wednesday.

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

It beginning to look a lot like rain for Christmas. The National Weather Service is putting the chances at 50 percent, with daytime highs well into the 40s. Christmas Eve could slip into the 50s. It's always a disappointment for Baltimore, but never a surprise to pass another Yuletide with asphalt rather than snow beneath Santa's runners. Only one in ten Christmases in Baltimore sees snowfall, and just one in four dawns with snow on the ground.

The weather service forecasters out at Sterling have assembled their annual statistical rundown on the chances for white Christmases in Baltimore, and a host of other Christmas weather trivia. Clip and save, and when the conversation flags at your office holiday party, you can amaze your friends with your Christmas weather expertise.

                        *** BALTIMORE ***

IF YOU EXAMINED THE WEATHER RECORDS FOR ALL 121 OF BALTIMORE'S
CHRISTMASES SINCE 1893 (WHEN SNOWFALL RECORDS BEGAN)... IT WOULD
SHOW A TYPICAL CHRISTMAS DAY IS PARTLY CLOUDY WITH A FROSTY EARLY
MORNING LOW OF 28 DEGREES AND AN AFTERNOON HIGH OF 43 DEGREES.
HOWEVER... FROM YEAR TO YEAR THE WEATHER CAN BE ANYTHING BUT
TYPICAL.

FOR THOSE WHO LIKE IT COLD... THE COLDEST WAS IN 1983 WHEN THE
TEMPERATURE FELL TO ZERO DEGREES. THAT WAS A COLD DAY INDEED AS IT
ALSO PRODUCED THE COLDEST HIGH TEMPERATURE FOR THE DAY... A FRIGID
12 DEGREES THAT AFTERNOON. THE FIVE COLDEST LOWS WERE:

           1983-  0 DEGREES
           1989-  7 DEGREES
           1980-  7 DEGREES
           1960- 12 DEGREES
           1998- 13 DEGREES

HOW ABOUT A WARM CHRISTMAS? THE WARMEST WAS A TOASTY 72 DEGREES IN
1964... WITH THE WARMEST LOW TEMPERATURE OF 48 DEGREES ON THE SAME
DAY. THE FIVE WARMEST HIGHS WERE:

           1964- 72 DEGREES
           1982- 70 DEGREES
           1932- 67 DEGREES
           1893- 67 DEGREES
           1965- 65 DEGREES

FOR SNOW LOVERS... A WHITE CHRISTMAS IS SOMEWHAT OF A RARITY IN THE
BALTIMORE AREA. INTERESTINGLY... ONE OF THOSE RARE EVENTS OCCURRED
THREE YEARS AGO WHEN A GENERALLY RAINY CHRISTMAS MORNING CHANGED
TO SNOW AT THE END OF THE EVENT DURING THE LATE MORNING HOURS. THERE
WAS ENOUGH TO MEASURE ONE INCH. THE FIVE SNOWIEST CHRISTMASES WERE:

           1909- 9.3 INCHES
           1969- 6.1 INCHES
           1902- 3.0 INCHES
           1962- 2.9 INCHES
           1935- 1.2 INCHES

A TOTAL OF 12 CHRISTMASES OUT OF 122 REPORTED MEASURABLE SNOW. THAT
AVERAGES OUT TO ABOUT 1 WHITE CHRISTMAS EVERY 10 YEARS... ONLY 10
PERCENT.

IF YOU INTERPRET A WHITE CHRISTMAS AS MEASURABLE SNOW ON THE GROUND
(AT LEAST A TENTH OF AN INCH)... THAT IMPROVES THE ODDS SOMEWHAT.
TWENTY NINE TIMES SNOW WAS ON THE GROUND CHRISTMAS DAY THAT EITHER
FELL THAT DAY... OR WAS ON THE GROUND FROM A PREVIOUS STORM. THAT
AVERAGES OUT TO ABOUT 1 WHITE CHRISTMAS EVERY 4 YEARS... 25 PERCENT.

IF YOU WOULD LIKE TO USE CHRISTMAS PAST TO GAUGE CHRISTMAS FUTURE:

           2004 -->  HI 31  LOW 17  MOSTLY SUNNY AND COLD
           2003 -->  HI 42  LOW 28  MOSTLY SUNNY AND BLUSTERY
           2002 -->  HI 38  LOW 32  RAIN WITH SOME SNOW/SLEET
           2001 -->  HI 40  LOW 23  PARTLY SUNNY AND COOL
           2000 -->  HI 27  LOW 17  SUNNY BREEZY AND COLD
           1999 -->  HI 32  LOW 14  MOSTLY SUNNY AND COLD
           1998 -->  HI 33  LOW 13  SUNNY AND COLD
           1997 -->  HI 56  LOW 41  PARTLY CLOUDY WITH RAIN SHOWERS


HAPPY HOLIDAYS!

Posted by Frank Roylance at 3:22 PM | Permalink | Comments (0)
Categories: Winter weather
        

The Winter Solstice arrives at 1:36 p.m. EST today, marking the official end of autumn and the start of the northern winter. For meteorologists, of course, winter began Dec. 1 and will end on Feb. 28.

But for the ancients, who paid far more attention to the sky than we do, the solstice marked not the start of winter, but the middle, the moment when the sun reached its southernmost point in the sky, and when the shortening and dimming of the days and the lengthening of the cold, dark nights came to an end.

It was a time for celebration - for Saturnalia in ancient Rome, a holiday which some believe Christians co-opted for their Mass and celebration of Christ's birth. It was a celestial milestone, celebrated by the Romans with a week of feasting, drinking, gift-giving and the decoration of evergreens as a symbol of life's persistence through the harsh winter.

Other cultures and religions have a great variety of parallel observances of the solstice.

After the solstice, they all knew, the sun would rise farther north each morning, and climb higher in the sky each day. The nights would begin to grow shorter, and the days longer. It was a time of year that held the first promise of spring, the return of the light and the renewal of life.

Of course, modern astronomers have a different perspective on the phenomenon, and explanations for why the darkest time of the year is not also the coldest. Here's a discussion of the science of the solstice and the seasons.

In Baltimore today, the sun rose at 7:23 a.m, and will set at 4:47 p.m.  That gives us 9 hours and 24 minutes of sunlight, and 14 hours and 36 minutes of darkness. But it only gets better from here.

Posted by Frank Roylance at 11:01 AM | Permalink | Comments (0)
Categories: Almanac
        

Would somebody tell me again, please, why Constellation Energy wants to get mixed up with Florida Power & Light?  Here's Constellation, based in Maryland, which hasn't seen a storm make a direct strike on its territory, at hurricane force, in like, forever. And here's FPL, which this year alone set a new record for outages from one storm. Hurricane Wilma caused 3.2 million FPL outages in October, about three-quarters of everybody that buys juice from that outfit.

And that came on top of Katrina, in August, which knocked out power to 1.4 million FPL customers - probably lots of the same people who later went dark again in Wilma.

OK, so it was a bad year. But wait. In 2004, 5.4 million FPL customers lost power in three hurricanes. Jeanne (1.7 million); Frances (2.8 million) and Charley (874,000).

I'm not making this up. It's from FPL's own Website .  And, while the record is no doubt incomplete, you should add in Irene (1999), which doused the lights for 1.4 million, or 45 percent of FPL's customers; Andrew (1992) which did the same. We won't mention Betsy in 1965 (49 percent), Cleo in 1964 (68 percent) or Donna in 1960 (51 percent). These repairs cost a fortune in manpower, overtime, accommodations, contractors and materials.

Look at the map, people. Florida is a peninsula. It sticks out into the I-95 of hurricane tracks. People are moving out of the place because they're sick of boarding up their windows, rebuilding their roofs and living out of ice chests. 

And what's the hurricane forecast like?  Hurricane specialists virtually everywhere say we're one decade into what they expect will be several decades of increased hurricane activity in the Atlantic. Here's Bill Gray's forecast for an active 2006. The 2005 Atlantic hurricane season was a record-breaker, with 26 names tropical storms and 14 hurricanes if I remember rightly.

I'm sure the two companies considered much bigger issues when they reached their decision to merge. Maybe FPL wanted an anchor someplace where customers keep paying because their meters keep spinning. Maybe that's why I'm not in mergers and acquisitions. But you can bet Constellation stockholders will have a different perspective on things when Florida goes dark again during the 2006 hurricane season.

Posted by Frank Roylance at 6:24 PM | Permalink | Comments (0)
Categories: Hurricanes
        

The National Solar Observatory, on Sacramento Peak in New Mexico, has captured an image of an odd-looking craft crossing in front of the sun's disk. The U.S. Space Command should scramble to explain the phenomenon. For more, click here.

Posted by Frank Roylance at 4:59 PM | Permalink | Comments (0)
Categories: Cool pictures
        

Looks like the slim chance we had for snow showers on Christmas Eve and Christmas Day has slimmed to none. The National Weather Service is now looking at a 40 percent chance for rain on Christmas Day instead. Best last-minute shopping day: Friday, with a high of 50 and low of 32.

So, if you're longing for a white Christmas, you'll have to head west or north. Try Deep Creek Lake, or maybe Erie, Pa. Actually, you wouldn't have to go that far. Just click here for a look at where the snow cover is, or was yesterday.

And here's what the folks at the Sterling Forecast Office are saying about the balance of the week:

"HIGH PRESSURE WILL KEEP THINGS QUIET THROUGH THE END OF THE WEEK. A
MODERATING TREND IN TEMPS IS EXPECTED BEGINNING ON FRIDAY AS SURFACE HIGH
SHIFTS SOUTHWARD. NEXT CHANCE FOR PRECIP NOT UNTIL PERHAPS CHRISTMAS DAY
AS A TROUGH AMPLIFIES OVER THE MID MISSISSIPPI VALLEY. AT THE MOMENT, IT LOOKS LIKE A
RAIN EVENT AS THERE IS NO ARCTIC AIR IN PLACE."

Too bad. Where is all that winter weather when you need it?

Posted by Frank Roylance at 10:39 AM | Permalink | Comments (0)
Categories: Winter weather
        

I was driving I-83 soutbound onto the Beltway toward Pikesville last week, when I was passed by a tractor trailer. Evidently, the trailer had not been moved since the most recent snow, and its top was covered in snow and ice.

As the trucker drove at about 60 mph, a sheet of ice about the size of a card-table top lifted off the top of the trailer, began to rotate high in the air, and then fell onto the pavement, where it shattered in front of me. I watched as the guy drove on, and he was clearly oblivious to what was happening behind him. Five or six times as I watched (from an increasing distance), another sheet of ice lifted off, spun and crashed to the pavement behind the truck. Each time, drivers behind the truck slowed, or swerved to avoid being struck.

If you think getting hit by one of those things would be without consequences, click here. I took this as a lesson - be sure to clear your car or truck of snow and ice before driving off. Even if the ice doesn't smash somebody's windshield and lacerate them, it could easily damage a following vehicle, startle the driver into sudden braking or swerving and cause an accident.

Has anyone else had a similar experience on the road with flying shards of ice?

Posted by Frank Roylance at 6:26 PM | Permalink | Comments (0)
Categories: Winter weather
        

Here's a remarkable shot of our region, snapped yesterday from orbit by NASA's Aqua Earth-observing satellite. You can see the thick storm clouds moving away to our south and east, and snow from last week's storms on the ground in the mountains to our west and north. But the sun was shining on Baltimore.

Just click on the image to enlarge it. Then rest your cursor over the picture until the "enlarge" button appears. Then click on that to blow it up even more.

I sometimes wish they would leave the state and international boundaries off these images, or at least allow users to toggle them on and off. It would be wonderful to see the Earth's surface as it really is - no political overlays. Just Earth.

Posted by Frank Roylance at 10:28 AM | Permalink | Comments (0)
Categories: Cool pictures
        

It could happen. The forecast for the rest of this week shows nothing but sunshine and seasonable temperatures. But at the end of the 7-day prognostication there is a glimmer - only a glimmer - of hope for some (dare we say it?) snow on Christmas Eve and Christmas Day. It's only a 30 percent chance, and the language includes both "rain and snow showers" for Saturday evening and Sunday as a new cold front blows in. But it's enough for now.

It's been 96 years since the Great Christmas Snowstorm of 1909. Here's how the weather service recalls that one:

"The "Great Christmas Snowstorm" struck the North Atlantic States hard. Maryland was on the southern edge with the Upper Eastern Shore receive over a foot and a half of snow. Delaware and eastern Pennsylvania averaged 20 inches. Philadelphia had 21 inches in 23 hours. A band of 25 inch snowfall stretched from Sudlersville in Queen Annes County to Dover, DE. Towson record 16 inches and Rockville 10 inches from the storm. Baltimore had 10 inches most of which fell on Christmas Day. Washington DC had around 5 inches. The storm did its greatest damage in New England. Winds gusted to 72 mph in Rhode Island with the storm and the combination of wind and snow damaged poles and wires. People were lost with their ships and a couple people drowned in tidal flooding from the storm."

But then there's no need to go too far with the idea. A nice, fresh coating of white will do fine.

Posted by Frank Roylance at 5:34 PM | Permalink | Comments (0)
Categories: Forecasts
        

Here's a handy roundup of all the activity during the record-smashing 2005 Atlantic Hurricane Season. Nice map, loads of data on most storms, some interesting links. I couldn't get some of the animations to work. Maybe you'll have better luck.

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

Looks like this winter storm to our south will stay there. It's headed out to sea, where mariners can expect some rough going today - winds 30 to 40 knots (34-46 mph) and seas 8 to 15 feet, rising to 50 knots (57 mph) and 21 feet along the Gulf Stream. Whew! Batten the hatches! Break out the dramamine!

You can check on conditions at bouy stations in the region by starting here and clicking on the bouy you want.

Portions of the lower Eastern Shore, and Southern Virginia had been warned to expect a bit of wet, windy weather, too. But it appears to have cleared the coast by early afternoon Here's the forecast for Virginia Beach.

Ocean City, too, looks to be in the clear.

Here's what the radar looks like. And here's the storm warning for coastal waters.

The weekend break in the bad weather allowed me to get outside yesterday and rake up the oak leaves that had been buried under the old snow. The snow washed away, but the leaves were still there, waiting patiently for me.

Except in the back yard, where half the grass remains in shadow most of the day, and where everything is still coated with snow and ice. So I raked the leaves off the grass in the sunny, autumn part of the yard. Then I found myself raking the snow and ice on the wintry side to grab what leaves I could from there. That was a first. Raking the snow.

Looking up, of course, I noted that there are still plenty of leaves in the trees. But then technically, I suppose it's still fall. This is too confusing.

Posted by Frank Roylance at 10:15 AM | Permalink | Comments (0)
Categories: Winter weather
        

Don't panic. It's a CHANCE of snow- 20 percent. And if it happens, it won't snow for long. It's just the skirts of a storm passing across the Deep South. Otherwise, the future looks pretty sunny and seasonably cold. Here's the forecast. And here's how the forecasters describe the Sunday snow threat:

"SLIGHT CHANCE OF LIGHT SNOW IN LOWER SOUTHERN MARYLAND AND CENTRAL
VIRGINIA SUNDAY FROM A STORM TRAVELING THROUGH THE SOUTHEAST STATES.
OTHERWISE... NO HAZARDOUS WEATHER IS EXPECTED."

Relax. Enjoy the weekend.

Posted by Frank Roylance at 7:12 PM | Permalink | Comments (0)
Categories: Forecasts
        

The ice storm that blew through here yesterday made a heck of a mess. It also dropped a lot of numbers into the weather records. Here are a few of them.

All that snow, sleet, freezing rain and plain-old rain at Baltimore-Washington International Airport came to 1.47 inches of melted precip.  The temperature was rising pretty much all day, climbing to an impressive 51 degrees just after midnight. That's 5 degrees above the normal daytime high for the date. After the storm passed, the temps dropped sharply, to 36 degrees by dawn.

My home weather station caught it all, except for the rain part. The rain gauge had clogged with leaves and ice. It clocked exactly 0.01 inch of precip all day, until I went out in my rubber coat - in the pouring rain - and cleaned it out. From then - about 9 p.m. - until the storm ended at about 3 a.m., it registered three-quarters of an inch. And the sump pump ran all night. Impressive.

Here are the snow and ice totals from across the region. Frostburg wins the snow prize, at 11 inches. Charlottesville, Va. wins for ice - they got an inch of the nasty stuff.

From the useless trivia department comes this observation: Tomorrow - Saturday, marks the 73rd anniversary of the snowiest december day on record for Baltimore. It was an 11.5-inch snowfall in 1932. Anyone remember that storm? Even I'm too young for that.

Posted by Frank Roylance at 7:02 PM | Permalink | Comments (0)
Categories: By the numbers
        

As you may have noticed, the WeatherBlog has been down all day, due to a "disk problem" at our weblog host's site. They're still putting things right, and trying to retrieve the most recent posts, which vanished into the ether. Thanks for your understanding.

Posted by Frank Roylance at 6:54 PM | Permalink | Comments (1)
Categories: Notes to readers
        

After a late start and a few pauses, the snow is falling steadily now across the region. Here is the latest tally of accumulations, mostly to our west and in Virginia. Forecasters still expect the precipitation to change to sleet and freezing rain for most of the region, at least briefly, with more snow and ice accumulations to the north and west, and less to the south and east.

Update at 2 p.m.: The precip has changed to rain in downtown Baltimore. But the air temperature at the Science Center is still 29 degrees, suggesting warmer air aloft, colder at the surface. That's the setup for freezing rain. Leave a comment and let us know what you're seeing where you are.

The region remains under an Ice Storm Warning until 7 a.m. tomorrow. Here's what AccuWeather is expecting from the storm. There's plenty of wet weather ahead. Here's the national radar loop.

As expected, most school systems have closed, and many businesses are following suit. With ground temperatures stuck below freezing, whatever falls appears likely to stick and/or freeze on contact. Watch for slippery conditions under foot (and tire). Iced trees will lose limbs and drag down power lines as they fall, causing power outages.

Here's the forecast map. The pink counties out west can expect 1 to 3 inches of snow before the precip turns to freezing rain. Ice accumulations could grow to a half-inch, which may cause a lot of problems out there. It will likely change back to snow before it all ends tonight, making things even more treacherous tomorrow.

The purple counties could get an inch or less of snow and sleet before the changeover to freezing rain. But cold surfaces will allow icing to the tune of a quarter- to a half-inch. More trouble ahead for those people. They could also see a brief change to snow before the storm departs.

The tan counties, including Baltimore and points south and east, will get less than a half-inch of snow. The precip will switch to freezing rain and leave a tenth of an inch or two of ice wherever it lands. Roads may be icy.

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

The predicted ice storm is likely to coat tree branches and every other outdoor surface in a glaze that will light up like a fairyland when the sun comes back out on Friday. Of course, it may also bring down a lot of branches. Either way, it could prove to be a huge photo opportunity.

The WeatherBlog invites you to upload your best to our Readers Photos gallery, found at the bottom of the Maryland Weather.com homepage. Don't send everything, mind you; just your best. Here are some examples from other storms. And please be careful. It will be slippery out there. And watch out for falling limbs and downed power lines.

Posted by Frank Roylance at 6:13 PM | Permalink | Comments (0)
Categories: Winter weather
        

The outlook for Thursday appears to be deteriorating. The National Weather Service has issued an ice storm warning for most of Maryland north and west of the Baltimore-Washington corridor. If the forecast holds up, watch for school closings, treacherous steps and sidewalks, road accidents, and power outages as the day goes by:

"THE COMBINATION OF VERY COLD AIR TO THE NORTH AND LOW PRESSURE
OVER THE GULF STATES WILL PROVIDE THE FUEL FOR A SIGNIFICANT ICE
STORM ON THURSDAY.

"PRECIPITATION WILL LIKELY BEGIN AS A PERIOD OF
LIGHT SNOW THURSDAY MORNING...AND THEN CHANGE TO SLEET. WARMER AIR
WILL BE DRAWN INTO THE AREA A FEW THOUSAND FEET OFF THE GROUND...
CAUSING PRECIPITATION TO CHANGE TO LIQUID. HOWEVER AT THE SURFACE
TEMPERATURES ARE EXPECTED TO STAY BELOW FREEZING THROUGHOUT THE
DAY...CAUSING RAIN TO FREEZE ON CONTACT ON ROADS...POWER
LINES...AND TREES.

"ICE ACCUMULATIONS BETWEEN 1/4 AND 1/2 INCH ARE
EXPECTED...WITH SOME LOCALLY HIGHER AMOUNTS POSSIBLE IN THE
COLDEST VALLEYS.

"POWER OUTAGES AND EXTREMELY TREACHEROUS DRIVING CONDITIONS ARE
POSSIBLE BY THURSDAY AFTERNOON.

"AS THE LOW PULLS NORTHEAST OF THE AREA FRIDAY...MORE COLD AIR
WILL BE DRAWN INTO THE REGION...CHANGING PRECIPITATION TO SNOW BEFORE
ENDING EARLY FRIDAY."

Harford, southern Baltimore, Anne Arundel, Howard and PG counties can expect a bit more warming, and a changeover to rain for a time by afternoon. Their forecast includes a winter weather advisory that reads like this:

"THE COMBINATION OF VERY COLD AIR TO THE NORTH AND LOW PRESSURE
OVER THE GULF STATES WILL PROVIDE THE FUEL FOR WINTRY WEATHER ON
THURSDAY. PRECIPITATION WILL LIKELY BEGIN AS A PERIOD OF LIGHT
SNOW THURSDAY MORNING...AND THEN CHANGE TO SLEET.

"WARMER AIR WILL
BE DRAWN INTO THE AREA A FEW THOUSAND FEET OFF THE GROUND...
CAUSING PRECIPITATION TO CHANGE TO LIQUID. HOWEVER AT THE SURFACE
TEMPERATURES ARE EXPECTED TO STAY BELOW FREEZING THROUGH MID
AFTERNOON...CAUSING RAIN TO FREEZE ON CONTACT ON ROADS...POWER
LINES...AND TREES. THE FURTHER EAST YOU GO THE MORE LIKELY
TEMPERATURES WILL RISE ABOVE FREEZING BY AFTERNOON...CHANGING
PRECIPITATION TO PLAIN RAIN. ICE ACCUMULATIONS OF AROUND 1/10 OF
AN INCH ARE POSSIBLE IN THE ADVISORY AREA.

"AS THE LOW PULLS NORTHEAST OF THE AREA FRIDAY...MORE COLD AIR
WILL BE DRAWN INTO THE REGION...CHANGING A CHANGE TO SNOW BEFORE
ENDING EARLY FRIDAY."

Posted by Frank Roylance at 3:57 PM | Permalink | Comments (0)
Categories: Winter weather
        

The latest forecasts for tomorrow's wintry storm seem to be shifting the worst of the snow and ice accumulations closer to the Baltimore region. Earlier forecast maps held the winter storm watches, and the more significant ice and snow accumulations west of Frederick County. Not any more.

The 11:30 maps have shifted them as far east as Carroll, Frederick and northern Baltimore counties. The blue counties can expect more significant accumulations of snow and ice (and the fender-benders, slip-and-falls, downed limbs and power outages that go along with it).

My guess? Expect school closings west of the metro area, and delays, at least, in the Baltimore suburbs. If Baltimore County still treated the Hereford Zone differently than the rest of the county, I'd predict closings up there, too. But alas, whatever the current regime decides will apply to all.

No matter what happens, it looks like we're in for a cold, wet, miserable Thursday. The cold air we've been coping with for the past several days is going to be overridden by warm, wet air as a storm system approaches from the south. That will mean rain, falling through a surface layer of very cold air, producing sleet and freezing rain. That's the worst. Freezing rain occurs when rain forms in a warm layer of air and falls through colder air and onto very cold surfaces. It freezes where it lands. That's what produces iced windshields, slippery steps and sidewalks and frozen door locks, downed limbs and power outages.

The amount of snow or ice that accumulates will depend on where you are, what path the storm follows as it tramps through the region, how much of the precipitation changes to plain old rain, and how long the stuff is falling on you.

Here's the forecast for BWI and the beige counties on the map.

Here's what part of the winter storm watch in the blue counties looks like:

"PRECIPITATION WILL START AS SNOW AND SLEET. HOWEVER...WARM AIR
WILL OVERRIDE THE COLDER AIR ABOVE GROUND LEVEL...CHANGING
PRECIPITATION TO FREEZING RAIN. LOOK FOR FREEZING RAIN TO OCCUR THROUGH THURSDAY AFTERNOON. AS THE LOW PULLS NORTHEAST OF THE AREA FRIDAY...MORE COLD AIR
WILL BE DRAWN SOUTHWARD...CHANGING PRECIPITATION OVER TO SNOW
BEFORE ENDING EARLY FRIDAY.

"SIGNIFICANT ICE ACCUMULATIONS WILL BE POSSIBLE BY DAWN FRIDAY.
WARNINGS AND ADVISORIES WILL LIKELY BE ISSUED THIS AFTERNOON."

All in all, a good day to stay home with good book and a pot of soup. The weekend, thank heaven, looks to be relatively sunny, with highs near 40.

It could be worse. Parts of Pennsylvania and New York State are looking at 6 to 12 inches from this storm. Here's AccuWeather's forecast map.

Posted by Frank Roylance at 11:34 AM | Permalink | Comments (0)
Categories: Forecasts
        

Time to dig the crampons and golf spikes out of the boot box. Look for an icy day Thursday. The National Weather Service is expecting this cold air to become entrenched across the region as the next coastal storm system moves in on top of it overnight Wednesday night into Thursday.

That could mean snow at first, but forecasters now seem to be edging toward a sleet, rain and freezing-rain scenario. Freezing rain occurs when rain falls from warm air aloft, through the cold air we're feeling at the surface. If so, it will freeze where it lands. Expect slippery steps and sidewalks, icy windshields, frozen door locks, the works. If this forecast works out, we could also see snapping tree limbs, fallen power lines and power outages. Got enough fireplace wood to keep you warm ?

Here's the weather statement issued at 5 p.m. today:

"...WINTER WEATHER EXPECTED THURSDAY...

"AN AREA OF LOW PRESSURE WILL TRACK FROM THE GULF COAST THURSDAY TO
THE DELMARVA PENINSULA EARLY FRIDAY. THIS LOW PRESSURE SYSTEM WILL
SPREAD A LARGE AREA OF PRECIPITATION ACROSS THE REGION EARLY
THURSDAY MORNING...AFFECTING BOTH THE WASHINGTON DC AND BALTIMORE
METROPOLITAN AREAS.

"THE PRECIPITATION IS EXPECTED TO MOSTLY BE IN THE FORM OF A MIXTURE
OF FREEZING RAIN AND SLEET. PRECIPITATION MAY CHANGE OVER TO RAIN
MAINLY ALONG AND EAST OF THE BLUE RIDGE MOUNTAINS THURSDAY
AFTERNOON. THE POTENTIAL OF SIGNIFICANT ICE ACCUMULATION WILL EXIST
IN SOME LOCATIONS.

"STAY TUNED TO NOAA WEATHER RADIO OR YOUR LOCAL MEDIA FOR UPDATES ON
THIS DEVELOPING WINTER WEATHER SITUATION. WINTER STORM WATCHES MAY
BE REQUIRED FOR PORTIONS OF THE AREA OVERNIGHT."

Here is AccuWeather's take on the storm .

Posted by Frank Roylance at 6:50 PM | Permalink | Comments (0)
Categories: Forecasts
        

December is nearing the halfway mark this week with temperatures averaging 7 degrees below normal at Baltimore-Washington International Airport. The month to date has averaged 32.1 degrees. The low so far is 18 degrees, reached on the 7th and again on the 8th. It was 20 degrees this morning at BWI and colder elsewhere. It was 15 degrees on my deck in Cockeysville.

Here are some other morning readings from across the region:

Patuxent River NAS:  27 degrees

Annapolis:  25

Salisbury:  23

Maryland Science Center:  21.9

Andrews AFB: 21

Martinsburg, W. Va.:  19

Aberdeen Proving Ground:  19

Hagerstown:  12

Frederick:  10

The average low  at BWI in this part of December is 28 degrees. The average high is 47 degrees.

This cold air mass will cause us problems late Wednesday into Thursday as a coastal low moves up from the South, bringing us a wintry mess of snow and ice. The storm will bring moisture and warmer air from the South, and drop it through a surface layer of this cold, Canadian air. That will create freezing rain, and some icing problems on Thursday and Friday.

Overnight lows will stay in the teens for a few days. The forecast calls for a low of just 13 degrees tonight - the lowest of the season so far - before rising into the 20s and 30s on Thursday and Friday. The highs will stick in the 30s through Thursday, but poke into the 40s for Friday and Saturday.

.

Posted by Frank Roylance at 10:50 AM | Permalink | Comments (0)
Categories: By the numbers
        

The annual Geminid meteor shower - usually one of the year's best except for the cold - will peak tonight and tomorrow night. They're normally visible all night. And the weather looks like it will cooperate with clear skies in the three hours after midnight.

Unfortunately, a bright, nearly-full moon this year will wash out all but the brightest of the shower's shooting "stars."  But if you can get up and watch between 4:30 a.m. and dawn, the moon will have set, darkening the sky enough to bring out the fainter meteors. Urban lighting will make these virtually impossible to see, so seek out a dark spot in the country for the best possible view. 

The Geminids usually run about 120 meteors per hour under ideal seeing condition - which we definitely do NOT have this year. Here's where to look. This shower is not associated with a comet, but rather with dust debris tossed off by the passage of an asteroid called 3200 Phaethon. Read more about the Geminids' history here.

Here's a report of an object that may have been a big Geminid, from the upper peninsula of Michigan. And here's a gallery of pictures of last year's Geminids, including several from George Varros, of Mt. Airy, Md.

Posted by Frank Roylance at 3:02 PM | Permalink | Comments (2)
Categories: Sky Watching
        

The 2.2 inches of snow recorded at Baltimore-Washington International Airport on Friday wasn't much to look at. But it did manage to set a new record for the date, breaking the previous mark of 1.0 inch, set way back in 1995.

So far this month the airport has recorded 5.7 inches of snow. That's more than three times the long-term average for the whole month (1.7 inches). The snowiest December on record for Baltimore was in 1966, when a total of 20.4 inches fell at BWI. Three dates in December 1966 set new daily snowfall records that still stand. They totaled 19 inches, including:

Dec. 13:  7.6 inches

Dec. 20:  3.0 inches

Dec. 24:  8.4 inches, and a white Christmas. Anybody remember that one?

Posted by Frank Roylance at 11:20 AM | Permalink | Comments (0)
Categories: By the numbers
        

The forecasters are having a hard time with their predictions for the hind end of this week's weather. But it's safe to say we can expect below-normal temperatures for the next couple of days, followed by some combination of snow, ice and rain as cold air pushes into the region, and a new storm center blows up the Atlantic coast.

The precipitation - whatever form it takes - should start overnight Wednesday into Thursday, and persist in varying incarnations into Friday. Here's the forecast discussion from the National Weather Service, which is full of uncertainty:

"PREVIOUS SHIFT INTRODUCED FREEZING RAIN/ICE PELLETS WITH THE SNOW.
CONDITIONALLY SPEAKING...IT'S HARD TO RULE OUT ANY OF THESE (PRECIPITATION) TYPES
AND HAVE KEPT WED NIGHT FORECAST AS IS. ON THURSDAY...AFTER ANY MORNING MIXED PRECIPITATION TYPES...COULD SEE A CHILLY RAIN FOR MOST PLACES...BUT JUST DON'T
HAVE THAT SORT OF CONFIDENCE RIGHT NOW AND KEPT THE MORE GENERIC
SNOW/RAIN CHANCES ON THURSDAY ... UNCERTAINTY ALSO EXISTS WITH THE TIMING OF THE EXITING PRECIP...AND WILL FOCUS MORE ON HOW FAST THE COASTAL LOW LIFTS OUT OF THE MID-ATLANTIC REGION. ...  MADE PRECIP-TYPE ALL SNOW THURSDAY NIGHT UNDER THE
ASSUMPTION COLDER AIR WRAPS IN ... AS THE COASTAL LOW  RACES UP THE NEW ENGLAND COAST. ."

Here's AccuWeather's take on the developing storm.

Posted by Frank Roylance at 10:48 AM | Permalink | Comments (0)
Categories: Winter weather
        

If the clouds part long enough this (Sunday) evening - and they should - step outside after dark
and get a look at the planets. Turn first in the direction of the sunset. That's Venus above the
southwestern horizon, a dazzling searchlight that outshines everything but the moon. It doesn't get
much brighter than that.

Now, look over your left shoulder for the moon above the eastern horizon. It's having a close encounter
tonight with Mars, still bright and coppery more than a month after opposition, and its closest approach
to Earth since August 2003.

You can read more about it at www.spaceweather.com

Posted by Frank Roylance at 11:52 AM | Permalink | Comments (0)
Categories: Sky Watching
        

Remember the old Sherwin-Williams Paint ads with the red paint enveloping the planet from the North Pole? Well, here's a very cool loop animation of snow and ice enveloping the Northern Hemisphere with the advancing season. It's all based on real data. Watch the snow spread across Russia, and the sea ice fill the Bering Straits and advance across Hudson's Bay. I love this stuff. We'll have to check on this one again in a month or so, when winter is really dug-in.

In the meantime, I notice that snow chances have reappeared in the forecast for Next Wednesday into Thursday. Until then, just sun and stars.

Posted by Frank Roylance at 2:16 PM | Permalink | Comments (0)
Categories: Cool pictures
        

Here's the sight that caught many eyes Sunday evening, as the crescent moon passed close to the planet Venus in the southwestern sky after sunset. That's Earthshine illuminating the "night" side of the moon - sunlight reflected off the Earth and bounced back onto the moon.

Venus is currently close to its brightest-possible appearance in the evening sky. Through a telescope, it is a brilliant crescent, for precisely the same reasons that the moon appears as a crescent in the image linked above. Venus is circling the sun, and is now between us and the sun, but well to the left and relatively close, which increases its apparent size and brilliance. We see the sunlight reflected off that slice of the planet's cloud cover that is illuminated. The rest is on the night side, and dark. You can read more about it here. be sure to click on the animation.

Posted by Frank Roylance at 10:45 AM | Permalink | Comments (0)
Categories: Cool pictures
        

That was quick. No snow yet when I hit the sack last night, and it was all over by the time I got up this morning. But last night's fast-moving storm managed to pile up enough snow and ice to make driving dangerous early this morning, and it prompted school officials to throw in the towel, as predicted. You can watch the storm pull through New England and out to sea on this radar loop.

Snow totals weren't far from the predictions, at least the lower end of the forecast ranges. The heaviest accumulations were out west - 7 inches in Berkeley Springs, W.Va., Hancock and Frostburg. Hunt Valley reported 4 inches. Owings Mills had 3.5. Carroll County received 3 to 5 inches. Harford got 3 to 4. Frederick saw 5-6. Here's a map with local accumulations.

Best advice for today? Get that mess shoveled off your steps and sidewalks. Cold weather will fill in behind the departing storm systems and whatever isn't shoveled or evaporated today will freeze and give you fits over the weekend. Look for a low of 18 tonight. Sunshine will warm daytime highs to the low 40s or upper 30s through Tuesday. But the overnight lows will sink back to the low 20s.

Thanks to everybody for their snow observations last night and this morning. Don't you people sleep? We'll try to do more  of that when we get some REAL snow later in the season. Thanks, too, for those who submitted photos to the Readers Photos corner at the bottom of the MarylandWeather.com page.

Posted by Frank Roylance at 10:17 AM | Permalink | Comments (0)
Categories: Winter weather
        

No snow yet in Cockeysville at 10:35 p.m. The weather service reported an inch and a half in Frostburg
by 9 p.m. Post a comment and let's see where the snow is falling. Later on, you can stick a ruler in the
snow and report back here on snow depths across the region, or any sleet or rain you're receiving. For
the latest snow reports from the National Weather Service, click here.

Posted by Frank Roylance at 10:44 PM | Permalink | Comments (10)
Categories: Winter weather
        

That's the latest from the National Weather Service forecast office at Sterling, Va. - 3 to 6 inches of snow by the time the storm ends at noon Friday. But there are a couple of "ifs" knocking around.

I just got off the phone with Richard Hitchens, a NWS hydrologist at Sterling drafted for storm duty tonight. He says a flow of relatively warm air aloft, arriving from the south, will change some of the precip from snow to rain and sleet as the night goes by. That's especially true from southern Anne Arundel County south. But one of the forecast models pushes the changeover farther north. That would diminish our snow totals, too.

Could we be surprised in the other direction? With deeper snows than forecast? That does not seem likely. The Midwest storm is expected to merge with another from the South that's due to form and intensify somewhere off the Virginia capes tonight. That event will crank up the moisture and energy levels of the storm. But Hitchens doesn't think that will happen early enough, or close enough, to send heavier snowfall our way. Look north. AccuWeather puts the heaviest snows well north of the big East Coast cities, from northeastern Pennsylvania across Central New England.

What does seem likely for us is a snowy morning rush hour, and at least some school cancellations. On the other hand, Hitchens said, "We are in an inexact science. Anything can happen."

Anyway, here's how the storm warning for metro Baltimore put it:

"(SNOW) HEAVY AT TIMES. STEADY ACCUMULATING
SNOW IS EXPECTED TO TAPER OFF BETWEEN 10 AM AND NOON FRIDAY. A
TOTAL OF 3 TO 6 INCHES OF SNOW IS EXPECTED WITH THIS STORM.

"PERIODS OF SLEET AND FREEZING RAIN ARE ALSO POSSIBLE DURING THE
EARLY MORNING HOURS FRIDAY...MAINLY ALONG AND SOUTHEAST OF THE
INTERSTATE 95 CORRIDOR. ANY ICE ACCUMULATIONS ARE EXPECTED TO BE
MINIMAL."

Here's the heart of the "heavy snow warning" for York County, Pa.:

"THE SNOW WILL FALL HEAVILY AT TIMES THROUGH EARLY FRIDAY
MORNING.

"BY SUNRISE ON FRIDAY...5 TO 8 INCHES OF FLUFFY AND DRY SNOW WILL
COVER MOST OF CENTRAL PENNSYLVANIA. THE SNOW WILL TAPER OFF TO
SCATTERED SNOW SHOWERS BEFORE NOON."

Here's AccuWeather's take.

And here's a preview of what's ahead from this storm, which hit St. Louis earlier today.

Posted by Frank Roylance at 6:33 PM | Permalink | Comments (0)
Categories: Forecasts
        

The National Weather Service forecasters in Sterling, Va. have posted winter storm warnings for our region as snow approaches from the Midwest. It's not a killer storm. We're talking 3 to 5 inches by morning at BWI, with 2 to 4 more during the day Friday - 5 to 9 total. Here's the forecast. But it's likely enough to disrupt everyone's routines tomorrow.

There's also still a chance that things could get rapidly much worse. The Midwest storm is only part of the setup. That storm is moving in parallel with another low-pressure center that's forming to our south. If the two merge, and tap into moisture and energy from the ocean, it could deliver much heavier snow for someone - maybe us, maybe to our north and east. Here's how AccuWeather sees it.

At any rate, here's the current NWS winter storm warning:

"THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A
WINTER STORM WARNING...WHICH IS IN EFFECT FROM 6 PM THIS EVENING
TO 12 PM EST FRIDAY. THE WINTER STORM WATCH IS NO LONGER IN
EFFECT.

"A WINTER STORM IS CURRENTLY TAKING SHAPE ACROSS THE OHIO VALLEY...AND
IS FORECAST TO ADVANCE INTO OUR REGION THIS EVENING. THIS STORM
HAS A POTENTIAL OF PRODUCING A MIXED BAG OF SNOW...SLEET AND
FREEZING RAIN ACROSS THE DC AND BALTIMORE METRO AREAS. TOTAL
ACCUMULATIONS OF SNOW AND SLEET OF 3 TO 6 INCHES ARE EXPECTED BY FRIDAY
MORNING.

"A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW...
SLEET...AND ICE ARE EXPECTED. THIS WILL MAKE TRAVEL VERY
HAZARDOUS. IF YOU MUST TRAVEL...KEEP AN EXTRA
FLASHLIGHT...FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN
EMERGENCY. STAY TUNED NOAA WEATHER RADIO OR LOCAL MEDIA FOR
UPDATES TO THE FORECAST."

OK. That's the warning for our area. The curious thing about it is that the warning covers Sterling's forecast area, which stops at the Mason Dixon Line. Just above that line, just north of Baltimore Harford, Cecil, Carroll and Frederick counties in Maryland, the warning is a "heavy snow warning." The NWS forecast office for those areas - in State College, Pa. - is looking for up to a foot of snow central Pennsylvania, including Adams, York and Lancaster counties, just north of the Mason Dixon Line. Here's how their warning reads:

"THE SNOW WILL FALL HEAVILY AT TIMES THROUGH FRIDAY MORNING.

"BY SUNRISE ON FRIDAY...5 TO 8 INCHES OF A FLUFFY AND DRY SNOW WILL
COVER MOST OF CENTRAL PENNSYLVANIA...WITH 8 TO 10 INCHES POSSIBLE
ON THE RIDGES.

"THE SNOW WILL TAPER OFF TO SCATTERED SNOW SHOWERS BEFORE NOON.
ADDITIONAL ACCUMULATIONS FRIDAY MORNING COULD PUSH THE TOTALS CLOSE
TO OR EVEN OVER ONE FOOT."

The more time you spend looking at these watches and warnings, the more you realize that the geo-political boundaries they use don't always make sense. They're convenient, maybe even necessary. But they're not always logical. I mean, does this map make sense?

Posted by Frank Roylance at 10:30 AM | Permalink | Comments (2)
        

This storm is of little or no consequence to anyone who doesn't ply the Atlantic in ships or breathe with gills. But Hurricane Epsilon - perhaps the final tropical storm of the still-undead 2005 Atlantic season - continues to perplex forecasters, who have been predicting its imminent weakening and disappearance for nearly a week.

Yet Epsilon, the unprecedented 26th named storm and 14th hurricane of the season, is still steering corkscrews around the mid-Atlantic Ocean, still at minimal hurricane strength. And it continues to exasperate the folks at the National Hurricane Center in Miami, who say the ocean water is too cold for this to be happening. The season ended a week ago. Now 5 days at hurricane strength, it is the longest-lived December hurricane on record, according to Weather Underground. The record - 4 days - had stood since 1887.

Here is the latest advisory. Here is the irrelevant forecast track. And here is the view from space. (Storm's in the upper left-center, but disappearing with darkness over the ocean.)

Epsilon was born and named as a tropical storm on Nov. 29. Here is a partial chronology of Epsilon statements from the hurricane center. It's pretty funny. All times are Atlantic Standard Time:

Dec. 1: 11 p.m.: (Tropical Storm) EPSILON MOVING NORTHEASTWARD AND SLOWLY WEAKENING

Dec. 2, 11 a.m.: EPSILON BECOMES YET ANOTHER HURRICANE IN THE RECORD BREAKING
   2005 ATLANTIC HURRICANE SEASON...BUT GRADUAL WEAKENING IS FORECAST TO BEGIN LATER TONIGHT OR ON SATURDAY.

Dec. 2, 5 a.m.: EPSILON MAINTAINS HURRICANE STATUS OVER THE COOL WATERS OF
   THE CENTRAL ATLANTIC...BUT GRADUAL WEAKENING IS FORECAST TO BEGIN ON SATURDAY.

Dec. 3, 11 p.m. (Saturday):...EPSILON STILL A HURRICANE BUT EXPECTED TO WEAKEN...

Dec. 4, 5 a.m.: ...EPSILON WEAKENS TO A TROPICAL STORM...ADDITIONAL WEAKENING IS FORECAST DURING THE NEXT 24 HOURS.

Dec. 4, 11 a.m.: ...EPSILON REGAINS HURRICANE STRENGTH...BUT FORECAST TO WEAKEN...

Dec. 4, 11 p.m.: ...EPSILON STILL A HURRICANE...

Dec. 5, 11 a.m.: ...HURRICANE EPSILON REFUSES TO WEAKEN...FUTURE INTENSITY
UNCERTAIN...

Dec. 6, 11 a.m.: ...EPSILON BARELY HOLDING ON TO HURRICANE STRENGTH...

Dec. 6, 5 p.m.: ...EPSILON HANGS ON AS A HURRICANE ... SOME GRADUAL WEAKENING IS FORECAST DURING THE NEXT 24 HOURS.

Dec. 6, 11 p.m.: ...EPSILON MAINTAINING STRENGTH AS IT CONTINUES SOUTHWESTWARD...BUT A RAPID WEAKENING TREND IS LIKELY TO COMMENCE BY THIS TIME TOMORROW.

Dec. 7, 5 p.m.: ...EPSILON REMAINS A MINIMAL HURRICANE WITH WEAKENING EXPECTED EARLY THURSDAY INTO FRIDAY...

Go Epsilon!

Epilog: Dec. 8: 11 a.m.: Epsilon has finally expired, becoming one with a cold front. Here is the final advisory headline from the National Hurricane Center:

...EPSILON WEAKENING RAPIDLY...THIS IS THE LAST ADVISORY...

...IT IS ABOUT TIME...

Posted by Frank Roylance at 10:52 AM | Permalink | Comments (0) | TrackBacks (3)
Categories: Hurricanes
        

The first winter storm watch has been posted for the next snowfall in Maryland, anticipated for late Thursday into Friday morning. Garrett Countians have been advised to expect 6 inches or more from the weather system that's approaching from the midwest.

Metropolitan Baltimore and Washington can expect the fast-moving snowstorm to begin early Friday morning, around 2 a.m., and wind down by 9 a.m. It will be plenty cold enough for an all-snow event. The accumulation will depend on the storm track, and the interaction with a coastal low moving our way from the South. For the moment, they're calling for "light to moderate" accumulations. Here's the advisory:

"COMPLEX DOUBLE LOW STORM WILL LIKELY BRING SNOW TO THE REGION LATE
THU INTO FRI MORNING. AMOUNTS AND POSSIBLE FREEZING RAIN OR SLEET
MIXING WILL DEPEND ON HOW THE TWO LOWS INTERACT WITH ONE ANOTHER.
THERE WILL BE A SYNOPTIC LOW MOVING OUT OF THE MIDWEST AND PASSING
THROUGH PA. THAT SFC LOW WILL FADE WHILE A SECONDARY COASTAL LOW OFF
SAVANNAH DEVELOPS AND BECOMES THE MAIN LOW AS IT RACES NE.

"SO FAR THE GENERAL PATTERN WOULD FAVOR A LIGHT TO MODERATE SNOW FOR
THE REGION. IT HAS THE POTENTIAL TO BE GREATER... BUT THERE ARE NO
INDICATIONS THAT THE STORM WILL BE ANYTHING MORE THAN ANOTHER FAST
MOVING SNOW OVER THE REGION. STILL A RANGE OF POSSIBILITIES THOUGH...
FROM A DC SPLIT WITH MOST OF THE (northern) LOW PRECIP STAYING NORTH AND THE
COASTAL LOW PRECIP STAYING SOUTHEAST OF THE REGION...TO A MORE NEGATIVELY
TILTED UPPER LOW THAT WOULD MAKE THE COASTAL LOW STRONGER AND KEEP
IT CLOSER TO THE COAST WITH MORE SNOWFALL FOR US."

AccuWeather expects 3 to 6 inches at least, with much more if the storm slows or other cards fall into place. Here's their read on the situation. The engine behind all this, AccuWeather's John Kocet says, may be a "split" jet stream, which is bringing us cold and energy from the north, and moisture and more energy from the South. Whatever, we seem to have snow, hazardous driving and probably school closings in our Friday future.

Here's the snow-cover map for Tuesday, showing the effects of Monday's storm.

Posted by Frank Roylance at 10:16 AM | Permalink | Comments (0)
Categories: Winter weather
        

No one is commiting to it yet, but there are increasing hints among the weather gurus this evening that Maryland could see a major snowstorm - perhaps 6 to 10 inches - late Thursday into Friday.

AccuWeather, typically more aggressive in its forecasting than the National Weather Service, says it isn't ready to call the storm yet. Here's what they are saying about it. But they're not shy about noting that Joe Bastardi, their chief winter-weather guy, is predicting a big storm, one they're comparing to the February 1979 storm that dropped 20 inches on Baltimore.

The NWS forecast mentions only a chance of "snow showers" for the same period. They have issued a "special weather statement" noting the possibilities for a significant storm. But the background chatter mentions models runs showing enough moisture in the system to produce 6 to 10 inches:

"...MODEL SUITE IN GOOD AGREEMENT WITH RESPECT TO A
TROUGH APPROACHING FROM THE WEST LATE THURSDAY. FETCH FROM THE
EASTERN GULF OF MEXICO AND ATLANTIC REMAIN IMPRESSIVE AND MAY
SUPPORT THE RETURN OF THE BAROCLINIC ZONE AND CYCLOGENESIS OF A
COASTAL CYCLONE. POPS (probability of precipitation) WILL HAVE TO BE RAISED AS THE EVENT NEARS SHOULD THE GUIDANCE REMAIN CONSISTENT.

"AS FAR AS A FEW DETAILS OF THIS SYSTEM...THE 12Z GFS/NAM/CANADIAN
MODELS INDICATE .5-1.5" OF LIQUID PRECIPITATION. MEANWHILE...THE
GARCIA METHOD USING THE 12Z GFS INDICATES A GENERAL 6-10" POTENTIAL.
WILL GO AHEAD AND ISSUE A SPECIAL WEATHER STATEMENT (WBCSPSLWX) AND
INCLUDE MENTION IN THE HAZARDOUS WEATHER OUTLOOK (WBCHWOLWX)."

Nice, huh? A rule of thumb (not always applicable) equates an inch of liquid precipitation in a winter storm to 10 inches of snow.

Posted by Frank Roylance at 6:42 PM | Permalink | Comments (0)
Categories: Winter weather
        

What would you think if you looked up and saw a sky like this one? End of the world? Close encounters of the cloud kind? They're called mammatus clouds. Here's an explanation of how and when these surprisingly benign clouds form. And here's a gallery of more amazing photos. The etymology of the term you can figure out for yourselves.

Posted by Frank Roylance at 1:09 PM | Permalink | Comments (0)
Categories: Cool pictures
        

Here's one of the most spectacular images to come back to Earth so far from NASA's plucky Mars rovers - still working after nearly two years on the surface. (They were only expected to last three months.) Scroll around this shot and explore the view. Click on it to get a larger version. It's amazing. And, on any clear evening this month you can still see coppery Mars with your own eyes, as it gleams high overhead, a mere 51 million miles away and receding.

Posted by Frank Roylance at 11:32 AM | Permalink | Comments (0)
Categories: Cool pictures
        

The 6-inches-plus accumulation recorded in St. Mary's County during yesterday's snowstorm - and 5 inches in Charles County - seem to top the charts for Maryland, although the Towson-to-Hunt Valley area came in with a respectable 4 inches. Here's a rundown on accumulations around the region.

There were 4 inches on my deck this morning in Cockeysville. The overnight low on my weather station touched 21 degrees around sunrise. Here's how it looked at BWI, the station of record for Baltimore since 1950. And here's what the nation's snow cover looked like just in advance of the storm's arrival. And here's the 31-day animation of advancing snow and ice. Pretty cool. And here's the map from Sterling of Monday's storm totals. Kind of low-tech, but it works. Here's the snow cover map for Dec. 6, showing the impact of Monday's storm.

Overall, I'd say this was the perfect snowstorm. It covered the ground and laced the trees, but pretty much left the streets and sidewalks bare. And there may be enough sunshine today to melt most of what remains, despite relatively cold temperatures. We can expect highs in the 30s for the rest of the week, and lows in the teens and 20s.

The sunshine will continue through Thursday. But the forecast holds the possibility for a significant snowstorm Thursday night into Friday. The weather service puts the chances at just 40 percent for now. Beyond that, they're looking for another coastal storm to approach on Monday, with more snow. Here's how the folks at Sterling put it:

"LOW PRESSURE WILL DEVELOP OVER THE SOUTHEAST AND APPROACH THE AREA
THURSDAY NIGHT AND MOVE TO THE NORTH OF THE AREA...WHILE ANOTHER LOW
ORIGINATING FROM THE GULF (will) ... PASS TO THE SOUTH. PRECIPITATION
SHOULD REMAIN ALL SNOW, WITH COLD HIGH PRESSURE IN PLACE AHEAD OF THE
SYSTEM. FOR NOW...WILL CARRY 40 POPS (probability of precipitation)  FOR THURSDAY

NIGHT AND FRIDAY. THIS SYSTEM WILL MOVE OFFSHORE BY FRIDAY EVENING AND HIGH

PRESSURE WILL REGAIN CONTROL OVER THE REGION. NEXT SYSTEM LOOKS TO BE YET
ANOTHER COASTAL THAT APPROACHES THE FORECAST AREA ON MONDAY."

Here's how AccuWeather calls the next storm.

Posted by Frank Roylance at 10:39 AM | Permalink | Comments (0)
Categories: Winter weather
        

The kids are home from school early. Commuters will flee work early as the flakes thicken. So go home, get out the camera and take pictures. Then, send us your best first-snowstorm-of-the-season images. Just scroll down to the bottom of the marylandweather.com main page, to the "Readers' Photos gallery. Then click on "Submit your weather photo" and follow the directions. Hundreds - nay, thousands - of readers will see your work.

Posted by Frank Roylance at 3:07 PM | Permalink | Comments (0)
Categories: Winter weather
        

Here we go, Baltimore. Killer flakes are falling in downtown Baltimore as of 2:30 p.m. The first real snow threat of the 2004-2005 season is gathering strength to our south. NWS meteorologist Brian Guyer says Baltimore can expect 2 to 4 inches by morning. Given Baltimore's tendency toward snow panics, we should expect an early evening rush hour this afternoon, although Guyer says the snow will have no real impact on driving until after dark, when the temperatures get colder and the snow is expected to get heavier. "The end of the rush hour is when we will experience the worst conditions," he told me.

Sunset is around 4:45 p.m. these days. So far, at 2:30, the Expressway looks quiet. But when office workers spot the snowflakes, they'll start to bail.

At 1 p.m. there was already light snow in Richmond, in Accomack on the Virginia Eastern Shore, at Ocean City, Md. and in Salisbury. Things probably won't get really cranked until this evening.

The Sun's Jacques Kelly, the youthful half of the famed Jacques Kelly-Fred Rasmussen team of obituary writers, points out that if snow materializes today, it will be the third Dec. 5th in four years on which we have received snow in Baltimore. I checked, and he's right:

Dec. 5, 2002: 7.4 inches

Dec. 5, 2003: 3.0 inches (and another 3.8 inches the next day).

Dec. 5, 2004: No snow. Partly cloudy skies.

Dec. 5, 2005: Wait and see.

The watches and warnings have painted a very colorful weather map this morning. The heaviest snow is anticipated to the south of the Baltimore and Washington metro areas. Here's what the developing storm looks like from space. Here's what the snow looks like at Va. Commonwealth University, in Richmond, where it is already falling.

And here's the gist of the snow forecast for Calvert, Charles and St. Mary's counties:

"LOW PRESSURE DEVELOPING OVER THE GULF STATES WILL TRACK
NORTHEASTWARD OVER THE CAROLINAS THIS AFTERNOON..AND THEN WELL
EAST OF THE DELMARVA TONIGHT.

"SNOW WILL INCREASE IN INTENSITY THIS AFTERNOON...AND CONTINUE
INTO THE EVENING HOURS. BETWEEN 3 TO 6 INCHES OF SNOW IS EXPECTED
TO FALL ACROSS THE CENTRAL SHENANDOAH VALLEY. 4 TO 8 INCHES WILL
FALL ACROSS CENTRAL VIRGINIA AND SOUTHERN MARYLAND...INCLUDING
CHARLOTTESVILLE...FREDERICKSBURG...AND SOLOMONS.

"THIS AMOUNT OF SNOWFALL COULD CAUSE SIGNIFICANT AND WIDESPREAD
TRAVEL PROBLEMS. THE WEIGHT OF THE SNOWFALL COULD ALSO CAUSE SOME
POWER OUTAGES. IF YOU LIVE IN THE WARNED AREA...IT WOULD BE A
GOOD IDEA TO CHECK YOUR WINTER STORM SURVIVAL KIT. ALSO...IF YOU
MUST TRAVEL DURING THE HEIGHT OF THIS STORM...CARRY A WINTER
EMERGENCY KIT IN YOUR CAR."

For those of us in the Baltimore-Washington corridor, the forecast is slightly less dire - just 2-4 inches in metro Baltimore. Here's the heart of it:

"LIGHT SNOW WILL DEVELOP THIS AFTERNOON FROM SOUTH TO NORTH. THE
HEAVIEST SNOWFALL WILL OCCUR IN A BAND DURING THE EVENING
COMMUTE...AND TAPER OFF SOON AFTER MIDNIGHT.

"BETWEEN 3 TO 5 INCHES OF SNOW IS EXPECTED TO FALL ACROSS METRO
WASHINGTON INTO THE SHENANDOAH VALLEY. BETWEEN 2 TO 4 INCHES WILL
FALL ACROSS METRO BALTIMORE. AN INCH OR TWO IS EXPECTED TO FALL
ACROSS THE NORTHERN SHENANDOAH VALLEY AND EASTERN WEST VIRGINIA
PANHANDLE...INCLUDING WINCHESTER...MARTINSBURG...AND HAGERSTOWN.

"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."

The fact that this is likely to be an all-snow event testifies to the cold air moving into the region. Passage of this storm will not bring relief from the cold, either. They're loooking for overnight lows in the 20s and teens all week. Expect the mercury to bottom out at 15 degrees in Baltimore Wednesday night into Thursday. There's even discussion of a possibility for lows in the single-digits Thursday morning. Time to open the Code Blue shelters for the city's homeless.

And the chatter among forecasters suggests a chance for another snowstorm Thursday night into Friday. And all this talk of snow and cold in the Northeast has been heard, even by the oil market. I hope your tanks are full.

Buckle up!

Posted by Frank Roylance at 11:09 AM | Permalink | Comments (0)
Categories: Winter weather
        

Like Glenn Close in "Fatal Attraction," the 2005 Atlantic Hurricane Season refuses to die. Hurricane Epsilon actually strengthened over the weekend, despite the official end of the season on Nov. 30, a threat of snow in Maryland, cooler waters in the Atlantic and the prognostications of a weakening by the National Hurricane Center. The compact storm is still blowing with sustained winds at 80 mph, after stuttering over the weekend and dropping briefly below hurricane force. It is now 545 miles west southwest of the Azores, moving toward the east southeast at 8 mph.

There is still no threat to land. Epsilon's hurricane winds extend a mere 25 miles from the center. Tropical storm winds spread 115 miles from the center. The storm is forecast to turn back toward the southwest this week - a real wanderer, this one.

Here is the latest advisory. Here is the forecast track. Epsilon is the 26th named storm and 14th hurricane of the 2005 season, both all-time records.

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

This day ended with such a beautifully clear sky, I had to doubt whether the National Weather Service
was still expecting snow Monday. We were driving down I-95 this evening, after brunch with friends in
Philadelphia, and we were dazzled by the crescent moon and the most brilliant view of Venus any of us
is likely to see. They were paired in a deep blue dusk sky for most of our drive south. It was clear
enough to see "Earthshine" in the darkened portion of the moon's disk. (That's sunlight, bounced off
the Earth and back to the moon, illuminating the "night" side of the moon's surface.)

Snow tomorrow? It sure didn't look like it to me.

But the prognosticators at the forecast office in Sterling are sticking to their guns. Here's what they're
saying this evening:

"LOW PRESSURE WILL DEEPEN OVER THE SOUTHEAST STATES TONIGHT AND MOVE
OFF THE CAROLINA COAST ON MONDAY. PRECIPITATION ASSOCIATED WITH THIS
SYSTEM WILL BEGIN TO OVERSPREAD THE REGION EARLY MONDAY MORNING. AT
THE SAME TIME...COLDER AIR WILL FILTER IN QUICKLY TONIGHT CAUSING
THE PRECIPITATION TO FALL IN THE FORM OF SNOW. AT THIS TIME...THERE
IS THE POTENTIAL FOR MODERATE SNOW ACCUMULATIONS CAPABLE OF
PRODUCING TRAVEL PROBLEMS AND SCHOOL CANCELLATIONS. PRELIMINARY SNOW
TOTALS OF 3 TO 6 INCHES ARE POSSIBLE BY TUESDAY MORNING OVER THE
METROPOLITAN AREAS OF WASHINGTON DC AND BALTIMORE."

And here is a bit of their background discussion, edited (by me) for length and clarity:

"BANDING CONSIDERATIONS WILL ALLOW FOR THE
HIGHEST TOTALS FROM NORTH CENTRAL VA ... TOWARD LOWER
SOUTHERN MARYLAND AT 4 TO 8 INCHES. THIS ASSUMES AN ALL SNOW FORECAST (as
computer model) PROFILES SUGGEST...ALTHOUGH AM A LITTLE WORRIED
THAT INITIAL ACCUMULATIONS MIGHT BE ON GRASSY AREAS GIVEN RELATIVELY
WARM GROUND RIGHT NOW. WILL GO WITH 3 TO 6 INCHES ALL OTHER
LOCATIONS EAST OF THE BLUE RIDGE...INCLUDING THE DC AND BALTIMORE
METRO AREAS...AND ALSO THE POTOMAC HIGHLANDS AND SHENANDOAH VALLEY.

"A VERY IMPORTANT POINT
HERE IS THAT THIS IS ONE OF THOSE SITUATIONS WHERE THERE WILL BE A TIGHT
GRADIENT/SHARP CUTOFF BETWEEN HEAVY SNOWFALL AND MUCH LOWER AMOUNTS.
THIS ADDS TO THE UNCERTAINTY IN THE SNOWFALL AMOUNT FORECAST AS WELL...AND
WILL BE VERY TRACK DEPENDENT."

In other words, it could snow here quite a bit, from Monday into Tuesday. Or maybe not,
depending on where "here" is.

Posted by Frank Roylance at 10:24 PM | Permalink | Comments (0)
Categories: Winter weather
        

The National Weather Service has posted a heavy snow warning for Garrett County until 8 p.m. today. That means the folks out there can expect 4 inches of snow or more, "severe" winter conditions and dangerous driving. Allegany County is under a snow advisory, with 1 to 3 inches possible by 8 tonight. Expect snow-covered roads if you're headed out there today for the weekend.

I saw some flakes in the air on my drive into Baltimore this morning as scattered snow showers crossed the region. Our forecast looks even snowier, as meteorologists predict a series of low-pressure systems tracking through the region starting Saturday night.

We can expect snow, sleet and/or rain starting Saturday night. Sunday looks rainy, but snow chances rise again for Sunday night, Monday and Tuesday.  Here's what the chatter looks like from Sterling: (My edits, for clarity, in parentheses.)

"NOT ANTICIPATING ANY APPRECIABLE SNOW AMOUNTS AND/OR ADVISORIES WITH THIS FIRST STORM (Saturday into Sunday).

"A SECOND AND STRONGER WAVE OF LOW PRESSURE POSES A SIGNIFICANT THREAT FOR MODERATE TO HEAVY SNOWS ACROSS THE ENTIRE REGION MONDAY. (Computer model) DATA
SHOWS PRETTY GOOD CLUSTERING (agreement). TRACKING A SURFACE LOW ACROSS FAR NORTHERN GEORGIA AND INTO NORTH CAROLINA MONDAY. (Air masses) ARE SUFFICIENTLY COLD
ENOUGH FOR SNOW MOST AREAS EXCEPT RIGHT ALONG THE COAST AND FAR SOUTHERN AREAS."

Oh boy.

For the latest discussion from Sterling, click here.

Posted by Frank Roylance at 10:44 AM | Permalink | Comments (1)
Categories: Winter weather
        

Tropical storm Epsilon made it to hurricane strength today - two days after the official end of the 2005 Atlantic hurricane season. The storm - the 14th hurricane of the season - is no threat to land. It's swirling in the mid-Atlantic between Bermuda and the Azores. Tops sustained winds are blowing at about 75 mph. The storm is moving toward the northeast at 14 mph. It's expected to begin weakening again in the next day or two.

Here's the latest advisory. Here's the forecast track, in case anyone cares. And here's the view from space. Epsilon is in the upper right-hand corner.

Here's what the National Hurricane Center wrote yesterday about the 2005 season. The numbers do not reflect Epsilon's ascension to hurricane status this morning.

"THE 2005 ATLANTIC HURRICANE SEASON IS THE MOST ACTIVE ON RECORD.
TWENTY-SIX NAMED TROPICAL STORMS FORMED...BREAKING THE OLD RECORD
OF 21 SET BACK IN 1993. THIRTEEN STORMS BECAME HURRICANES...
BREAKING THE OLD RECORD OF 12 SET BACK IN 1969. SEVEN OF THE
HURRICANES BECAME MAJOR HURRICANES...CATEGORY THREE OR HIGHER ON
THE SAFFIR-SIMPSON HURRICANE SCALE...INCLUDING THREE...KATRINA...
RITA...AND WILMA...WHICH REACHED CATEGORY FIVE INTENSITY. THIS IS
THE FIRST TIME SINCE 1851 THAT THREE CATEGORY FIVE STORMS HAVE BEEN
KNOWN TO OCCUR IN A SEASON. THE SEASON ALSO INCLUDED THREE
DEPRESSIONS THAT DID NOT REACH TROPICAL STORM STRENGTH.

"IN CONTRAST...BASED ON THE AVERAGE FOR THE LAST 40 YEARS...IN AN
AVERAGE SEASON THERE WOULD HAVE BEEN 11 NAMED STORMS...6 HURRICANES
...AND 2 MAJOR HURRICANES."

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

In the summer of AD 1054, sky watchers in China, Japan and the American Southwest looked up and noticed a spectacular new star. It was as bright as the full moon and visible in the daytime for a month. They recorded the event in writing and on rock pictographs. It was actually the titanic explosion of an old star - a "supernova."  And it lit up like a flare. The Chinese called it a "guest star." It's only happened twice since, and not for 400 years. Good thing. If a similar event occurred close enough to Earth, it would fry us all.

Today, astronomers can still see the remnants of that 1054 explosion as the stuff continues to billow and expand into space. The gas and glowing debris are known as the Crab Nebula, and the Hubble Space Telescope has taken an absolutely stunning new picture of it. You can see it here.  (Click on it to enlarge it.) There's more to read here. I've already made it my new desktop background image. It's a beaut.

Posted by Frank Roylance at 6:00 PM | Permalink | Comments (0)
Categories: Cool pictures
        

And so it begins. Forecasters are watching the development of a relatively weak storm in the southern Plains that will move through here late Saturday into Sunday with a mix of snow and rain. What you see through your windshield will depend on where you're driving, with the best chances for snow in the northern and western counties, and more rain to the south and east. Here's the forecast from the National Weather Service in Sterling, Va.

Meanwhile, AccuWeather is hyping the chances for another, more potent storm that its forecasters see developing in the South early next week, and then moving up the East Coast with lots of moisture. Again, whether you see snow or rain will depend on how cold it is where you are. It's our perennial wintertime forecasting headache in these parts.

However you look at it, it looks like we're in for a cold, wet weekend, with more possible next week.

But cheer up. You could live on the West Coast. They're in for a bit of foul weather for the next few days. Snow in Seattle?

Posted by Frank Roylance at 11:16 AM | Permalink | Comments (0)
Categories: Winter weather
        

November expired last night after a relatively mild run in Baltimore, and an inch short of average rainfall.

Temperatures for the month averaged 48.1 degrees, which was 2.6 degrees warmer than the 30-year norm. The daily highs ranged from 77 degrees on the 6th, to just 34 degrees on the  day after Thanksgiving. Overnight lows ran from a high of 53 degrees on the 9th, to a frigid 19 degrees last Saturday morning.

Precipitation totaled just 2.12 inches. That's a full inch short of average for November. That extends a period of dry weather that began in September, broken only by the Oct. 7 deluge caused by the passage of the remnants of Tropical Storm Tammy.  The month's precipitation came in just three events. Baltimore-Washington International Airport saw a little more than a half-inch of rain at mid-month - on the 15th and 16th. There was nearly an inch of rain on Nov. 21-23. And we got almost two-thirds of an inch on Tuesday at BWI.

Snowfall totalled a whopping half-inch, on the 23rd. But you probably slept through it unless you live in Western Maryland, where it was way deeper and lasted longer.

We had plenty of sunshine. Skies at BWI were clear to partly cloudy on 22 days. They were overcast on just 8 days in November. The peak wind was a 52-mph gust on Thanksgiving Day.

Since the launch of the new format at the National Weather Service's website for the Sterling, Va. forecast office, I haven't been able to figure out how to provide direct links to the month's weather observations. But you can go to this page and learn to navigate to the data you need. For past months, click on "Preliminary climatology," then "Baltimore," then "Archived data," then the month you're looking for. Then click on "GO."

For observational data for the current month, click on "most recent" instead of "archived."

Posted by Frank Roylance at 10:46 AM | Permalink | Comments (0)
Categories: By the numbers