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Posted at 05:27 PM ET, 02/17/2012

PM Update: Mild Saturday, snow possible Sunday

For yet another day, February brought us milder than average temperatures, passing the 50 degree mark. Saturday is no different with 50+ afternoon temperatures likely for the 10th time this month. But Sunday is another story. A cold front drapes itself over the region as low pressure approaches from the southwest, bringing a chance of snow, or possibly rain. Winter storm watches have been posted for the potential of at least 5” of snow in western and central Virginia, including Charlottesville and Culpeper.

Through Tonight: Clear sailing with gradually falling temperatures. Temperatures around 50 at sunset steadily fall through the 40s by midnight and into the mid-30s downtown by morning, with upper 20s in the colder suburbs. Winds are light from the north.

Saturday and Saturday night: The weekend starts off swimmingly. Mostly sunny skies and a light breeze from the south boost temperatures into the 50-55 degree range Saturday afternoon when a few high clouds trickle in. Clouds increase Saturday night as a back door cold front drops southward. Lows range from near 30 in the colder suburbs to the mid-30s downtown.

Sunday: There is a chance of snow and/or rain in the morning, with some snow likely in the afternoon. However, if the precipitation intensity is light, rain may fall instead. There is a chance of a heavier period of snow late Sunday afternoon and Sunday evening. Temperatures are steady in the mid-to-upper 30s into the afternoon, possibly falling back into the low 30s if steadier precipitation arrives.

Accumulations: Depending on the intensity of the precipitation, some snow acccumulation is possible by Sunday evening. The most likely accumulation amounts will be 1 to 4” (lowest north, highest southwest). However, accumulation scenarios almost as likely include:
* less than 1” (especially northern suburbs)
* more than 4” (especially southwestern suburbs)

For more detailed information on the Sunday snow potential, see these blog posts:

Inside a nearly impossible winter weather forecast

Sunday snow situation: could be boom or bust

See Brian Jackson’s forecast through the weekend. And if you haven’t already, join us on Facebook and follow us on Twitter. For related traffic news, check out Dr. Gridlock.

Afternoon model update: After the European model blanked us, the NAM and GFS model both simulated light to moderate amounts of snow Sunday afternoon and evening. The NAM’s liquid equivalent precipitation, however, dropped from 1.0” last night, to 0.75” this morning to just 0.5” in this afternoon’s run. The GFS has held steady with about 0.3-0.4” liquid equivalent (afternoon run was a little wetter compared to the morning). Its surface temperatures, however, are mostly above freezing. That means snow accumulations would probably be limited to mainly grassy areas if it’s right (except if precipitation becomes heavy) and some rain may mix in, especially at the onset.

We will have our next update around 11:15 p.m. tonight, possibly even an accumulation map :)

By  |  05:27 PM ET, 02/17/2012

Categories:  Forecasts

 
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