The weather observed at SAN FRANCISCO, CA (KSFO) at 03:56 AM PDT was: The skies were cloudy. Temperature: 55F ( 13C) Dewpoint: 52F ( 11C) Relative Humidity: 88% Winds from the SW (240 degs) at 6 mph. Pressure: 1012.8 millibars. Altimeter:29.91 inches of mercury. The prevailing visibility was 10 miles.