See PM Update for the forecast through the weekend.
10:20 p.m. update: Snow showers we’ve been watching for hours have finally made it to the I-95 area. Reports of light snow have recently been quite common locally. Flakes are flying in D.C.
9:30 p.m. update: The band of mainly light snow is approaching the northwest Beltway. It will push across the immediate area over the next hour or two. This band remains broken and it has been pulsing in intensity. Any accumulation could end up hit-and-miss.
8:55 p.m. update: This snow band is still taking its sweet time moving in, but it will get here eventually! Snow is reaching a Leesburg, Va. to Mt Airy, Md. line and moving out of places like Frederick, Md. The somewhat broken band of snow activity will shift through the inner north and west suburbs over the next hour and should be moving into the immediate area near or after 10 p.m. (surprise, another shift later!).
For the most part, we can expect scenes like below. There are some bursts here and there which could push spots to a half inch or even an inch if it lines up right. Any untreated roads will become snow-covered where snow falls.
8:10 p.m. update: Snow is on the move, and it’s dropping east southeast through western parts of the area. Some moderate activity is showing up on radar lately as it heads through Loudoun County and into Montgomery County. This band moves into the immediate area over the next hour or so.
7:20 p.m. update: Snow is moving east of the I81 corridor and entering parts of the area. Places like Frederick will be seeing flakes shortly if not already. The most recent short-range HRRR run suggests that the band of snow will push through the western suburbs from now through about 9 p.m., entering D.C. around that time. Radar more or less backs up that idea. Based on radar and modeling, a dusting of snow seems more likely than an inch in most areas.
6:30 p.m. update: Snow is being slow to move into the area. It’s mostly hanging out west of the Blue Ridge, but should edge into western locations over the next hour. The slow movement probably argues for a later arrival in the immediate area than earlier estimates, perhaps more like between 8 and 9 p.m. around the Beltway. This activity is mainly light, but we’ve seen reports of moderate bursts in places like Martinsburg, West Virginia.
5:50 p.m. update: Snow still is about two hours or so from the Beltway. Reports from the west around I-81 suggest snow is mostly light. We have a report of a light coating west of Winchester, where the snow is picking up in intensity some.
5:15 p.m. update: Light snow has advanced east of I-81 with some flakes reported around Winchester. The timeline given below (4:15 p.m. update) remains on track. Radar and short-term modeling suggest the snow may be mostly light, although we cannot rule out a heavier burst or two.
4:15 p.m. update: Radar shows snow showers approaching the I-81 corridor in western Virginia. Short-range modeling continues to suggest arrival around 6 p.m. in Frederick and Leesburg, between 7 and 8 p.m. in D.C.’s suburbs west of I-95, and between 8 and 8:30 p.m. east of I-95. Snow should last two hours or less. It should hit the Beltway around 8 p.m.
Original post, from 9 a.m. and updated at 11:45 a.m. and 2:30 p.m.
The National Weather Service says “stay informed and be ready to adjust travel plans”. This is sage advice as snow showers Friday evening have the potential to make a mess of area roads.
As a strong Arctic cold front charges into the region this evening, a line of snow showers is likely to move through that may quickly cover road surfaces with an icy, slick film.
The National Weather Service has issued a winter weather advisory, cautioning “untreated roads will become snow covered and icy…making travel difficult.”
As of mid-afternoon, the latest modeling brings snow inside the Beltway between 7:30 and 8:00 p.m.
We are not expecting a lot of snow and it will pass quickly but, as we’ve seen from past events (see Jan. 20, the Wed. night before the blizzard), it doesn’t take substantial amounts to lead to major problems on the roads when temperatures and road surfaces are subfreezing – as they will be tonight.
Short-term models suggest snow could move into our western areas around Frederick and Leesburg as early as around 5-6 p.m., areas inside the Beltway around 7:30 or 8 p.m., and areas east of the Beltway around 8 or 8:30 p.m. This timing is subject to change but, for planning purposes, if you want to avoid this snow burst and the travel issues it may bring, try to reach your destination an hour BEFORE the snow is scheduled to start.
Snow shouldn’t last more than about two hours in any location, but a quick dusting to an inch is possible. Locally higher amounts of 1-2 inches can’t be ruled out where snow falls most heavily.
Waiting until the snow ends to travel to your destination is risky. In the event roads become gridlocked, backlash delays would be considerable.
There is, of course, the CHANCE that these snow showers break up and miss some areas and/or don’t amount to much. But this is a situation that calls for erring on the side of caution when making planning decisions.
Temperatures tumble after the snow passes, falling through the 20s overnight as winds crank up.
(This post, originally published at 9 a.m., was updated at 11:45 a.m. and 2:30 p.m.)