The weather observed at SAN FRANCISCO, CA (KSFO) at 04:56 AM PDT was: The skies were mostly clear. Temperature: 52F ( 11C) Dewpoint: 49F ( 9C) Relative Humidity: 89% Winds from the WNW(290 degs) at 8 mph. Pressure: 1012.9 millibars. Altimeter:29.91 inches of mercury. The prevailing visibility was 10 miles. The maximum temperature in the past 6 hours was 54F. The minimum temperature in the past 6 hours was 52F.