The weather observed at PHILADELPHIA, PA (KPHL) at 02:54 AM EDT was: The skies were mostly clear. Temperature: 39F ( 4C) Dewpoint: 21F ( -6C) Relative Humidity: 48% Winds from the W (260 degs) at 12 mph. Pressure: 1017.2 millibars. Altimeter:30.04 inches of mercury. The prevailing visibility was 10 miles.