A double whammy of snow and bitter cold is poised to descend over the D.C. area as an arctic front barges through late Saturday night into Sunday morning.
A winter weather advisory is in effect for snow, which could drop up to 2 inches or so in the Beltway region and a bit more toward Annapolis and Baltimore, perhaps falling heavily for a time predawn Sunday. The snow will be followed by the coldest air of the season Sunday into Monday, with wind chills dipping into the single digits Sunday night. Temperatures will then not surpass freezing until Tuesday.
The combination of snow and falling temperatures could make travel hazardous Sunday, especially in the hours just before sunrise. The snow should end between 6 and 10 a.m. in most of the area, but freezing temperatures mean it will stick around. Allow extra time to reach Sunday morning activities, and some may be canceled.
The amount of snow that may fall remains somewhat uncertain because the Beltway area and locations just to the south and west are along the periphery of where models project accumulation. For this reason, Montgomery and Fairfax counties are under a winter weather advisory but Prince William and Loudoun counties, where accumulating snow is less certain, are not.
Slight shifts in where the edge of accumulating snowfall sets up would alter amounts, and changes in the forecast remain possible.
Our Capital Weather Gang forecast calls for a coating to 2 inches in the Beltway area but 1 to 3 inches from Annapolis to the Baltimore and to the north, where some localized higher amounts are possible. Areas south and west of Fairfax County are more likely to see a coating or less.
Timeline
10 p.m. Saturday to 2 a.m. Sunday: Chance of snow, mainly north and west of the Beltway. Little accumulation, except a possible coating in northern Maryland. Temperatures: 34 to 39.
2 to 4 a.m. Sunday: Snow spreads over most of the area, except for far Southern Maryland. Snow may briefly begin as rain near and east of Interstate 95. Light accumulation is possible, especially on grassy areas. Temperatures: 31 to 36.
4 to 6 a.m. Sunday: Snow, possibly heavy at times, especially near and east of Interstate 95. Accumulation is likely, including on roads. Periods of low visibility. Temperatures: 28 t0 33.
6 to 10 a.m. Sunday: Snow tapers off from northwest to southeast, ending in the Beltway area by 7 or 8 a.m. Temperatures: 24 to 29.
Temperatures provided are lowest northwest of the Beltway and highest into Southern Maryland.
Impacts
Because much of the snow will fall while Washingtonians are sleeping and on a weekend, this event will bring fewer disruptions than one that might occur during the workweek. Still, expect delays and cancellations of Sunday morning activities. Some flight delays are also likely.
This will be a relatively short-duration snow — falling steadily for just a few hours in most locations. The most difficult period for traveling will be between about 4 and 7 a.m., when the snow may be heavy, especially along and east of I-95 north of D.C.
It would be a good idea to clear any snow from walkways and driveways by midafternoon Sunday, when the sun may assist with melting even with air temperatures hovering in the 20s and winds gusting over 30 mph. By late afternoon, temperatures will be falling, and everything will freeze hard by the evening.
On Capital Weather Gang’s winter storm impact scale, this rates a Category 1 out of 5, or nuisance.
Around D.C., the snow will be of an average consistency; neither powdery nor particularly wet. A drier more powdery snow is anticipated toward northern Maryland, while Southern Maryland will have a wetter snow.
How the forecast could go wrong
Snowfall could be more than anticipated if the edge of the heavier precipitation expands farther south and west than current projections. That could mean up to 2 to 4 inches in the Beltway area and accumulating snow reaching deeper into D.C.’s southern suburbs.
But if the edge of the snow is sharp and a bit more to the northeast, the Beltway area and southern suburbs could see just a coating or less, and even D.C.’s northeast suburbs might get only an inch or so. Lighter precipitation would also mean temperatures don’t fall as fast (steady snow falling through the sky cools the air), which would limit how much would stick.
Here’s how much snow different models project for the Beltway area, which gives a sense of the range of possibilities:
- Canadian: 4 to 5 inches
- American: 3 to 4 inches
- European and NAM: 2 to 3 inches
- HRRR and SREF: Around 2 inches
- German and American AI: 1 to 1.5 inches
- RRFS and European AI: 1-inch
- UK Met: Little or no accumulation
Note that these amounts fall under the assumption that all snow will stick, while a bit of it will melt initially due to above-freezing temperatures.
Wes Junker, Dan Stillman, Ian Livingston, Camden Walker and Jeff Halverson contributed to this report.
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