Metro is limiting bus service because of the snow and icy roadways, while airports are still allowing flights to come and go.
Transit officials say Metrobuses are operating only on emergency snow routes Saturday afternoon and evening. That means buses will only travel on main roadways where streets are passable, until further notice.
MetroAccess service was canceled for Saturday, but officials say Metrorail is operating on a normal schedule. De-icer trains may be used Saturday evening to keep rails free of ice.
Hundreds of salt trucks and snow plows are treating roads in D.C., Maryland and Virginia. But officials say the cold temperatures mean the snow is sticking quickly. Transportation officials are urging drivers to stay off the roads.
While the snow is making the roadways forbidden, the skies are still open. Dulles and Reagan airports remain open, allowing flights to come and go. There are a few delays, as crews clear the runways and may continue to throughout the night.