Parts of the D.C. area could see their first frost of the season as an advisory is in effect until Sunday morning. In Virginia, parts of Culpeper, Fauquier, Frederick, Loudoun, Prince William, Spotsylvania and Stafford counties and the cities of Manassas and Manassas Park are covered by the advisory until 9 a.m. Sunday. Parts of Carroll, Howard and Montgomery counties in Maryland are also under the frost advisory.