All federal and Washington-area county and city offices will be closed tomorrow, Christmas Day. However, emergency and essential services will be be available at all times. Virginia state, local and city employes in Northern Virginia will have a half-day holiday today, as will many federal employes.

Schools: All area schools will be closed for the winter holiday until Jan. 4, 1982, when classes resume.

Mail: There will be no regular mail service on Christmas. Special delivery and express mail deliveries will be made.

Liquor: In Virginia and Montgomery County, liquor stores will be closed on Friday. Liquor stores in the District and Prince George's County are not required to close.

Refuse: No trash will be collected in the metropolitan area on Friday. In the District, Falls Church, Fairfax and Arlington, Friday pickups will be made today. Friday Supercan collections in the District will be made on Saturday. In all other jurisdictions where collections are made on Fridays, pickups will be made on the next normally scheduled day.

Banks: All banks in the area will be closed Christmas.

Libraries: All area libraries will be closed Christmas. Libraries in Fairfax, Arlington and Montgomery counties also will be closed Saturday and Sunday. In Prince George's and Alexandria, facilities are closed today as well as Christmas. They will be open normal hours over the weekend. Facilities in the District will be closed on Saturday.

Courts: All area courts will be closed Christmas.

Transportation: Metrobus and Metrorail will operate on Sunday schedules and off-peak fares will be in effect on Christmas. The Silver Spring Ride-On will also run on a Sunday schedule. The Gaithersburg Ride-On will not be operating.

Parking: Weekday parking and traffic regulations in the District will not be in effect Christmas. Parking meter fees will not be required.