Surface observations

Data from the National Weather Service, made available here by the UAlbany Department of Atmospheric and Environmental Sciences

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.