Some sleet (frozen rain drops) may initially mix in with the rain on Tuesday morning, with steady, soaking light to moderate rain continuing throughout the evening (image above is from the latest North American Model, or NAM, courtesy Tropicaltidbits).
Temperatures on Tuesday morning will be flirting with the freezing mark across the sheltered valleys of the Appalachians as well as locations across extreme northern Maryland near the Pennsylvania border. Some slick spots are possible during the morning rush hour before temperatures warm above freezing in these locations.
The latest Euro (image below) shows central and northern Pennsylvania picking up 3 to 5″ of snow by tomorrow evening.
The same model shows between one-half and one inch of rain falling across the DC Metropolitan Area by Tuesday evening. We need the rain.
High Temperatures Tuesday: More in line with mid-January. Will be a raw day with temperatures finally reaching the mid 40s tomorrow evening in DC.