Thursday, March 3, 2005

Mid-day update: Marching in Washington

Washington has long been noted for its Marches, and as Josh explains below, this one promises to be every bit as exciting as many in the past. Except for a sun angle more typical of World Series time in October (Did you notice how BRIGHT the snow was Tuesday?), today could easily be mistaken for a mid-January day whose temperature is about 5 degrees below the average for that time of year. Yesterday's high was only 37. That was as cold as, or colder than, 20 days of this past January and all but 2 days of last month. Brisk northwesterly winds gusting up to 30 mph should make it feel even colder than that. The winds are generated by the pressure difference ("gradient") between a large high-pressure area stretching from the upper Midwest all the way to the Gulf of Mexico and the low pressure area which brought our snow on Monday, still spinning over the Maritime provinces of Canada.

How cold can it get in DC in March? The all-time low of 4 was set on the 4th in 1873. On the other hand, the lowest record maximum for any date in March is 77, with an all-time high of 93 on the 23rd in 1907. So, if you want to experience all the seasons in Washington, come back each March, and you'll eventually see just about every kind of weather except tropical storms. Some years, you might even see spring!

At noon, temperatures around the area ranged from 32 at Leesburg to 39 at Culpeper, within a degree or 2 of those at the same time yesterday. Winds were gusting as high as 26 mph. We're on track for a high in the upper 30's and a low tonight about 20.

Tales from the Weather Grill
In our last episode, we revealed some of the secrets behind Momma Nature's management of the Weather Grill. Unfortunately, that wasn't the whole story. In fact, it's downright chaotic there. As we said, she goes out and buys the very best ingredients: crispy cold air, ripe juicy tropical moisture, the liveliest energy ("vorticity") available. She hires the most skilled technicians to develop partial-differential equations and program them into the tastiest recipes. But then, something seems to go terribly wrong. Perhaps she forgets where she put the recipe and leaves the ingredients sitting around until they spoil and have to be thrown out. Maybe she rushes around too fast and everything turns out undercooked. Or, she mixes the ingredients, puts them into the oven, and then spends so much time talking on her cell phone to the other goddesses that she doesn't hear the timer go off, and dinner is burned beyond all recognition. What can you do? She's a quirky lady, but she's the only Nature we've got. Even though we keep complaining, snow fans or snow-haters alike, we love her anyway, and we keep coming back to see what she's dishing out today. If you don't like your meal, please don't complain to us. We don't cook it; we only interpret the menu from the clues Momma gives out. If you want, you could try filing a report at Zagat's.

Washington Wacky Winter Weather Wimpiness
Recent discussion of the wimpiness of Washington's response to winter weather (or the threat thereof) reminded me of the fast-food commercial of a decade or so ago which went something like this:
Geezer 1: "When I was a kid, we had to walk to school 10 miles in the snow. And it was uphill both ways. In fact, we didn't even have shoes on our feet."
Geezer 2: "Feet, you had feet?"

Monday, February 28, 2005

Storm updates...


By 4pm, snow reports had tapered off to light intensities in the metro area. Shortly after 5, radar showed an area of snow with some breaks extending from just north of Charlottesville northeastward across the DC area. As this area moves through in the next couple of hours, snowfall will decrease and become more intermittent, possibly mixing with or changing to sleet or freezing rain in some places. There is a chance of more flurries or light snow tonight as an upper-air disturbance now over the Midwest moves toward us. For some snow measurements made during the day, check out the NWS Public Information Statement.
4:00pm: This afternoon's surface weather map showed a respectable low-pressure area off the coast about due east of the Virginia/North Carolina border continuing to bring in a flow of moisture off the Atlantic. The area of snow continues on radar from south of Charlottesville northeastward through DC and surrounding counties and across all except southeasternmost Maryland. Dulles reported heavy snow for a third hour at 3pm, while reports of moderate snow outnumbered those of light snow in the metro area.
Here in MoCo outside the Beltway, the picnic table has about 2 to 2.5" of accumulation. Pavement is mostly snow-covered but wet and slushy in places.
2:30pm: Snow has picked up in intensity over much of the area in early afternoon. Radar continues to show snow extending to the southwest of DC to at least Charlottesville, which was still reporting light snow. The rain/snow line has moved slowly northward north of Richmond on I-95 and across to near the mouth of the Potomac River. Dulles has reported heavy snow for the last 2 hours and other locations have light to moderate snow. Here in Greater Potomac, snow is definitely heavier; lawns and shrubs are thoroughly coated. The picnic table has about an inch of accumulation on the eyeball scale. Streets and driveways are lightly coated. The wind at Cape Hatteras is now from the west-northwest and the barometer was rising, as the storm center continues to move gradually away.


Snow will diminish in intensity during the evening. Total snow amounts will be near the low end of the predicted range, or somewhat lower in some areas.

Scroll down to the previous post for earlier history. Also, scroll down to the bottom of Jason's post below for the latest on closings and other useful links.

Storm updates...


1:00pm: At 12:30, radar showed snow continuing across the DC metro area, with additional snow extending to the southwest to well south of Charlottesville, which was reporting light snow. This area of snow was moving generally toward the northeast. The rain/snow line has remained fairly steady since early morning just north of Richmond on I-95 and extending northeastward. Ft. Belvoir was reporting moderate snow and the other local reporting stations had light snow. Besides Charlottesville, other VA stations reporting snow included Staunton and Lynchburg with light snow and Roanoke with moderate snow. In MD, snow was light at Baltimore and Andrews AFB, moderate at Annapolis. The wind at Cape Hatteras was from the north-northwest and the barometer was steady, indicating that the storm continues to move gradually away.
We will continue to see snow through the afternoon in most of the area. Depending on the intensity of the precipitation and the amount of mixing with sleet or rain, snowfall amounts will be on the low end of our predictions.
Scroll down to the bottom of Jason's post below for the latest on closings and other useful links.


Here's a dirty little secret: Momma Nature runs a sloppy kitchen down at her Weather Grill. She hasn't been cited for any code violations lately, not since she got that honking new supercomputer to help keep track of things, but it does get a bit out of hand there at times. The staff is very temperamental, and they don't always see eye to eye. It was an especially rowdy scene recently. All weekend long, the European chefs were arguing with the American ones over which recipe to use. The ingredients were on hand in large quantities for an exceptional meal, the biggest event of the season in the mid-Atlantic region:
  • crispy cold air
  • ripe, juicy tropical moisture
  • some of the liveliest vorticity (energy) on the planet
But, there was hot dispute over exactly what to prepare. The Europeans were in favor of a more wintry menu, with low pressure staying off the coast and colder air giving snow for us. The Americans favored a more traditional springtime menu, with the low pressure area moving inland and warmer air giving us rain. Tempers flared; the Europeans became so upset that they began threatening to keep the low so far out to sea that there wouldn't be enough heavy snow to satisfy all the customers who had made reservations because they were counting on a snow day. As time wore on, though, the Europeans began to convince the Americans of their point of view. Finally, Momma herself stepped in to settle things once and for all, but it was too late to get new menus printed with all the latest details. We'll just have to listen carefully as the waitpersons recite the daily specials.

We'll keep you continually updated as things develop. Remember our motto, "We keep hitting the page reload button so you don't have to!"

However the forecast turns out from your point of view, here's a bit of humor from the Washington Post's Style Invitational contest:
What's the definition of "Chiropractors-Christmas", taken from a page heading in the Yellow Pages directory?
"A forecast of freezing rain and heavy, wet snow."


At 11am, radar showed snow continuing across the DC metro area. Rain and showers were over the lower Chesapeake Bay and middle Eastern Shore. None of the official reporting stations in the immediate area were reporting anything heavier than light snow, but Charlottesville, Staunton, Lynchburg and Roanoke in VA all had moderate snow. In west-central Montgomery County, grassy areas are whitish, but mostly green/brown; streets are wet. Temperature has dropped about 1/2 a degree to just a bit above 32. The wind at Cape Hatteras was straight north and the barometer had stopped falling at 29.27" (991 mb). This indicates that the storm is beginning to move away from the coast.
10:00am: At 10am, radar shows snow continuing to break out across the DC metro area. At the official reporting stations, flurries at 9am had become light to moderate snow, with visibilities as low as 1/2 mile reported at Ft. Belvoir. Here in west-central Montgomery County, a light flurry which began shortly before 8 has given way to steadier and heavier snowfall, enough to moisten the pavement and begin to whiten some bare ground in the last 15 minutes. Temperature is just a fraction below 33. One interesting spot to watch as this storm continues to develop is Cape Hatteras, which has been reporting strong NE to NNE winds. The barometer there continues to drop at a pretty good rate, down 5 mb (.15") in the last 3 hours to 991 mb (29.27").

Seasonal Outlook

Latest seasonal forecast: Click here.

Latest 3-month temperature outlook from Climate Prediction Center/NWS/NOAA.