The weather observed at WASHINGTON DC, VA (KDCA) at 11:52 PM EDT was: The skies were cloudy. Temperature: 54F ( 12C) Dewpoint: 37F ( 3C) Relative Humidity: 54% Winds from the SE (150 degs) at 7 mph. Pressure: 1031.7 millibars. Altimeter:30.47 inches of mercury. The prevailing visibility was 10 miles.