Capital Weather Gang going with slightly below normal snowfall. Hopefully the link isn't paywalled.
Reagan National Airport (DCA): 10 to 14 inches (compared with a 15.4-inch average, 11-inch median)
Dulles International Airport (IAD): 14 to 18 inches (compared with a 22.0-inch average, 16 inch-median)
Baltimore-Washington International Marshall Airport (BWI): 14 to 18 inches (compared with a 20.1-inch average, 15-inch median)
Fairfax, Loudoun, Montgomery counties: 12 to 20 inches
Alexandria, Arlington and Prince George’s counties and the District: 10 to 16 inches
DEC +3
JAN +1-2
FEB +1-2
https://www.washingtonpost.com/weather/2020/11/18/washington-dc-winter-outlook-2020-21/