Cambridge Weather Summary September 2009 Based on 30 days' worth of half-hourly data recorded with rooftop sensors at the Computer Laboratory, Cambridge, U.K. Temperature (degrees C) Average: 15.1 Minimum: 5.2 (27 September 05:30) Maximum: 27.8 (08 September 15:30) Relative Humidity (%) Average: 73.8 Minimum: 36 (01 September 14:00) Maximum: 100 (11 September 02:00) Dew Point (degrees C) Average: 10.2 Minimum: 3.6 (20 September 15:30) Maximum: 17.7 (08 September 11:00) Atmospheric Pressure (mbar) Average: 1022.1 Minimum: 988 (03 September 05:00) Maximum: 1041 (10 September 20:30) Half-hourly Instantaneous Wind Speed (knots) Average: 5.5 Minimum: 0.0 (01 September 00:00) Maximum: 30.0 (03 September 18:00) Half-hourly Maximum Wind Speed (knots) Average: 13.0 Minimum: 0 (01 September 00:00) Maximum: 46 (03 September 15:30) Prevalent Wind Direction SW (28.5% of readings) Total Sunshine Hours 137.3 Total Rainfall mm 9.7