The weather observed at MADISON, WI (KMSN) at 01:53 AM CST was: The skies were clear. Temperature: 36F ( 2C) Dewpoint: 34F ( 1C) Relative Humidity: 92% Winds were calm. Pressure: 1017.6 millibars. Altimeter:30.03 inches of mercury. The prevailing visibility was 10 miles.