"Travel will be dangerous during this time, including the Wednesday morning commute," the weather service reported.
On Tuesday evening, Harford County could see one to two inches of snow and sleet, the weather service said.
Freezing rain will fall overnight through Wednesday morning, coating untreated roads and sidewalks in a sheet of ice, making travel dangerous.
Harford, northern Baltimore, Carroll, Howard, Montgomery and Frederick counties are all under winter storm warnings but the precipitation will be different. Snow, freezing rain and sleet will impact northeastern Maryland, while just freezing rain will hit the Baltimore-Washington area.
Temperatures will rise above freezing Wednesday afternoon, according to the weather service.