The weather observed at WASHINGTON DC, VA (KDCA) at 12:52 AM EDT was: The skies were mostly cloudy. Temperature: 62F ( 17C) Dewpoint: 45F ( 7C) Relative Humidity: 53% Winds from the CLM(CLM degs) at 0 mph. Pressure: 1020.9 millibars. Altimeter:30.15 inches of mercury. The prevailing visibility was 10 miles.