Well, I’m getting mixed messages. While some weather sources report that there is some 50 percent chance of scattered showers, the National Weather Service has opted to naysay and release a coastal flood advisory for the D.C. metropolitan area, including Southern Baltimore, the counties of Prince George’s, Fairfax, Arlington, Prince William, Calvert and St. Mary’s, and the cities of Alexandria, Falls Church and Manassas. The advisory, which is on until 8 p.m. tonight, calls for…