* Winter weather advisories issued for northern Fauquier, Loudoun, northern Montgomery, Howard, Frederick and Carroll counties from 3 a.m. to 1 p.m. Tuesday | School delays and closings *
Precipitation should exit the region from west to east around 10 to 11 a.m.
As far as the potential for snow accumulation, this looks like it could go one of two ways for the region west of D.C. and I-95 including Montgomery, northern Fairfax, Howard and eastern Loudoun counties:
1. We could see a burst of heavy enough snow that chills temperatures to around 32 or 33 degrees, cold enough for slushy spots on roads and sidewalks and up to an inch or two of snow on grass, especially in the northern to northwestern portions of those counties.
Or, 2. The snow may not be heavy enough or last long enough to chill temperatures below around 34 to 36 degrees, probably not cold enough for slushy spots and roads with less than inch on grassy areas.
Confidence is higher in the the potential for slush or a coating of snow on roads, and up to a couple of inches on grass, farther north Frederick and Carroll counties as well as north of Baltimore. From D.C. and I-95 to the east, temperatures should stay warm enough to limit accumulation potential to at most a whitening of the grass.
We’ve tried to capture our forecast in the map above, and will provide updates in the morning as conditions warrant.
Detailed forecast from earlier...
Today was a calm before the storm kind of day. Steel-gray skies foretold the coming weather. It will be a quick hit tonight through early Tuesday. But it’s also a dynamic storm, and rain could come down heavy at times tonight and flip to a moderate or heavy wet snow as it closes out Tuesday. North and west of Interstate 95 in particular, a coating to an inch or two can fall.
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Through Tonight: Odds of rain are up this evening. While rain will become more widespread, it won’t be too heavy until later evening. From the hours around midnight through the pre-dawn, rain might be heavy at times, adding up to an inch or so in many spots. Wind should increase out of the north and northeast through the night, gusting around 30 mph by dawn. Temperatures should fall through the 40s toward the 30s.
During the pre-dawn through sunrise, rain is expected to turn to heavy wet snow or a snow-rain mix from northwest to southeast.
Any elevated areas could get a quick coating or more, mainly on grass, but it can cause roads to become slushy in spots, as well. Snow may stay mixed with rain over southern Maryland but can add up to an inch or two through morning in northwest suburbs. Temperatures could briefly touch freezing in the coldest spots, but many will stay above, with a range of about 32 to 38 degrees for lows near sunrise.
View the current weather at The Washington Post.
Tomorrow (Tuesday): Moderate to heavy wet snow that begins in the pre-dawn through sunrise period west should continue to shift east into the morning commute period, with the potential for slushy roads persisting. Wet snow west and a rain-snow mix east should taper with time during the midday. Temperatures are expected to end up near the mid-40s for highs as winds blow from the northwest and skies try to clear a bit late in the day. Gusts of 30 to 35 mph are possible.
See Jason Samenow’s forecast through the weekend. And if you haven’t already, join us on Facebook and follow us on Twitter and Instagram. For related traffic news, check out Gridlock.
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Jason Samenow contributed to this post.
