A wave of low pressure will skirt to our south on Monday morning producing cold rain for most and the potential for some wet snow to mix in across the outer northern and western suburbs of DC and Baltimore during the afternoon as cold air begins to infiltrate our region. The image below shows rain (green) and areas of wet snow (blue/purple). Very light accumulations are possible on grassy surfaces well north and west of the Capital Beltway.
In the Allegheny mountains several inches of snow are possible where the National Weather Service has issued Winter Storm Watches. Further east, Skyline Drive may see a dusting to two inches of snow mainly on grassy surfaces if the snow can fall heavy enough to overcome the warm ground and marginal boundary layer temperatures.
In the Washington Area, a dusting of snow is possible on grassy surfaces across the northern and western suburbs including the Bull Run and Catoctin Mountains, Leesburg, Reston, Frederick, Germantown and Gaithersburg. The wet snow will be a conversational event only, with no issues expected on area roadways across the immediate metropolitan area (western Fairfax, Loudoun, northern Prince William and Montgomery counties).