A period of freezing rain, sleet and even snow is possible Tuesday, but rain also is a looming threat for travel tomorrow into Wednesday.
A Winter Weather Advisory remains posted for Montgomery, Fairfax and Prince William counties and points west through the Shenandoah Valley starting at 4am. The Advisory expires at 1 p.m. closer to the metro area and 4 p.m. for locations farther north and west where cold air may hang on later in the day.
Precipitation is expected to overspread the region late tonight into Tuesday morning. Very dry air at the surface will keep heavy precipitation from occurring until the air column saturates later in the day.
At this point, it appears light snow, sleet and freezing rain will become possible by the early morning hours after 4am in the far southwestern suburbs and later closer to the D.C. Metro.
Dew points are currently in the single digits and the air will need to saturate in the morning for precipitation to fall. With the saturation occurring, it will help cool the air, thus allowing for the onset of precipitation to be in the wintry form of snow, sleet and freezing rain. The D.C. Metro itself and places east may even experience a light wintry mix at the onset of precipitation but we're expecting a faster transition to rain by the late morning.
Frozen precipitation will change over to rain rather quickly closer to D.C. tomorrow, but may take a little while to change to rain in the western suburbs, particularly west of the Blue Ridge where cold air may pool in the valley through the afternoon.
Regardless, everything will change over to rain late in the day and into tomorrow night. Very heavy rain appears likely through Wednesday morning, with the potential of 2-3 inches of rain or even higher amounts possible.
This may cause some areas of flooding through Wednesday morning so stay tuned to the latest forecasts. A Flood Watch may be posted at some point tomorrow per the latest National Weather Service forecast discussion.
- Predicted Precipitation Totals
Gusty winds would be the next threat as the low intensifies over the the Northeastern U.S. Winds may gust up to 40mph+ at times Wednesday evening into Wednesday night. The highest gusts should be in higher elevations north and west of the city.
Thursday and Friday
Thanksgiving Day and Black Friday will be chilly, with highs in the upper 30s each day but also a lot quieter. Skies should be sunny and winds will begin to diminish come Thursday morning. High pressure should make for continued quiet conditions through the weekend.