“Places where the intensity of the snow stays light may only get a dusting of snow on grassy areas, while those who experience heavier snow may end up with a quick inch or two,” says Wes Junker, Capital Weather Gang’s winter weather expert. “While we favor the typical colder spots north and northwest of the city as having the highest chance of getting the most snow, the models have not shown enough consistency to say who, if anyone, in the area might see the heavier amounts.”
For the immediate metro area, the snow should target the predawn to early commuting period. East of the Capital Beltway, snow is expected during the heart of the commute.
* Snow should reach the Interstate 81 corridor between 1 a.m. and 4 a.m.
* Snow should reach areas west of the Beltway from Leesburg to Fairfax/Rockville between 3 a.m. and 6 a.m.
* Snow should reach the Beltway and Interstate 95 corridor between 4 a.m. and 7 a.m.
* Rain and snow should reach areas east of the Beltway (to the west side of the Chesapeake Bay) between 5 a.m. and 8 a.m.
In any given area, the snow should not last more than a few hours, quickly tapering off between sunrise and midday from west to east.
Before the snow starts, most areas should have temperatures above freezing. But once snow begins, temperatures should fall to near freezing or a little below. Where it snows harder, temperatures will fall faster. Where the snow is light, temperatures may stay a little above freezing, greatly reducing accumulation prospects.
“This is a tricky forecast, since how quickly the temperatures fall will be partly dependent on the snowfall intensity and because the models have differed on their temperature forecasts by a couple of degrees,” Junker says.
Once the snow exits, it will turn windy (gusts to 25 mph) and cold with temperatures holding in the low-to-mid-30s through Tuesday afternoon.
Temperatures falling into the teens to near 20 overnight Tuesday will cause any slush to refreeze.
It’s difficult to pinpoint where the heaviest snow will fall, so we’re broad-brushing amounts on our forecast map (see the top of this post). Almost everyone should see between a quick dusting and a couple of inches.
We slightly favor heavier amounts in our northern areas as some model forecasts have indicated more snow potential there, and those areas will be colder. Because this system will come through so fast, we see little potential for more than 2 or 3 inches anywhere.
Where snow falls heavily, it could be briefly problematic, limiting visibility and making roads slippery. The fact that snow may fall during the commute increases the risk of delays and disruption.
On the other hand, several factors will work to limit the impact of this event: 1) The ground is not cold. 2) Temperatures will be above freezing when the snow starts. 3) The snow won’t last long.
For some areas, this may turn out to be a nonevent: a little wet snow that doesn’t accumulate much.
Based on all of these factors, we’re rating this storm as a Level 1 nuisance event on our 1-to-5 winter storm impact scale. Having said that, we want to stress that conditions may widely vary, and some areas may contend with a period of hazardous travel early Tuesday.