It will be in effect from 2 AM to 9 AM on Wednesday.
...FREEZE WARNING IN EFFECT FROM 2 AM TO 9 AM EDT WEDNESDAY...* WHAT...Sub-freezing temperatures in the lower to middle 20s.* WHERE...Portions of central and northern Maryland and central and northern Virginia west of Interstate 95, and the eastern panhandle of West Virginia.* WHEN...From 2 AM to 9 AM EDT Wednesday.* IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.PRECAUTIONARY/PREPAREDNESS ACTIONS...Take steps now to protect tender plants from the cold.To prevent water pipes from freezing, wrap or drain or allow them todrip slowly.By The National Weather Service, Sterling, Va.