11:45 p.m. update: The GFS is not as “bullish” for snow as the NAM (it simulates about half as much precipitation), but – like the NAM and SREF – draws plenty of cold air down and still gives us accumulation Sunday night. Taking together all of today’s model information and the latest shifts, I’d say the chance of 1″ in the District has gone up from 50% to 70%, and the chance of at least 4″ has risen from 15-20% to 40% (from our afternoon update). (These percentages are even higher north and west of the Beltway). We’ll issue our “first call” accumulation map tomorrow afternoon and provide updates throughout the day. Snowy dreams, snow lovers.
(An interesting wrinkle with the GFS: it brings in a second wave of light snow Monday night into Tuesday morning with the trailing upper level system. Something to keep an eye on.)
10:30 p.m. update: Both the latest NAM and SREF models are pretty supportive of accumulating snow across the region Sunday night. They actually suggest a fairly rapid changeover from rain and focus the heaviest precipitation in the immediate D.C. area and our southern suburbs. This has a lot similarities to the March 3 event the way it’s shaping up. It’s looking like the odds of a few inches of snow or even a bit more have gone up. I’ll update one more time this evening after looking at the GFS.
We’re riding a never-ending weather roller coaster. After yesterday’s mid-30s, we bounced back to near 60 this afternoon. The wild ride continues this weekend with beautiful 60s Saturday but cooling to the 40s Sunday when light rain and snow develop towards the end of the day.
Through Tonight: Mostly cloudy and not nearly as cold as last night. Lows range from the upper 30s in the colder suburbs to the mid-40s downtown. Winds from the south around 10-15 mph gusting to 20 mph, become more from the west towards morning.
Tomorrow (Saturday and Saturday night): There may be some morning cloudiness, but sunshine becomes dominant in the afternoon. It’s very nice out there with highs in the low-to-mid 60s (upper 60s possible towards Fredericksburg). Winds are from the southwest and west around 10-15 mph, gusting to 20 mph at times. Some increasing high clouds Saturday night with lows near freezing in our colder suburbs, with mid-to-upper 30s downtown.
Sunday: Increasing clouds with a 30 percent chance of light rain or rain and snow mixed by late afternoon and early evening. Right now it looks like the bulk of our wintry weather holds off until after dark. Highs range from the low-to-mid 40s, but should fall back into the 30s when it starts precipitating.
See our detailed discussion on the possible winter storm for Sunday night into Monday. And if you haven’t already, join us on Facebook and follow us on Twitter . For related traffic news, check out Dr. Gridlock.
National Weather Service on Sunday night and Monday storm: Here’s the key take-home excerpt from the NWS’ afternoon discussion on what the D.C. area might expect Sunday night and Monday with respect to snowfall, which I agree with:
HIGHEST CONFIDENCE FOR MODERATE TO PERHAPS SIGNIFICANT SNOWFALL IS NORTH AND WEST OF I-95/METRO AREAS…MORE SO NORTH ALONG I-81 AS PRECIP SHOULD BE MOSTLY SNOW FOR THE ENTIRE EVENT. A BIT CONCERNED WITH THE CONTINUED SOUTHWARD SHIFT AND A PRECIP GRADIENT DEVELOPING AS OCCURRED DURING A SIMILAR EVENT A COUPLE WEEKS AGO. EITHER WAY…SITUATION IS TRENDING TOWARD A MORE SIGNIFICANT EVENT AND WATCHES MAY NEED TO BE CONSIDERED DURING THE OVERNIGHT SHIFT.
Terrific cartoon by CWG reader Karel Tiefel: