The weather observed at PHILADELPHIA, PA (KPHL) at 02:54 AM EST was: The skies were mostly clear. Temperature: 36F ( 2C) Dewpoint: 21F ( -6C) Relative Humidity: 54% Winds from the NNW(340 degs) at 10 mph. Pressure: 1024.4 millibars. Altimeter:30.25 inches of mercury. The prevailing visibility was 10 miles.