A mix of rain and sleet will overspread the Metropolitan DC Area between 3PM and 6PM. Locations along and north of interstate 66 in Virginia and route 50 in Maryland will change over to snow for several hours before ending as a mix of rain, sleet and snow. Further south, a brief period of snow and sleet is possible before a change over to rain. The northern and western outer suburbs will receive the longest period of snow before the precipitation tapers off and ends between 8 and 10 PM.
Here is the latest snowfall potential from the Weather Prediction Center: