Annual Weather Averages Near Janesville
Averages are for Janesville / Rock County, which is 4 miles from Janesville.
Based on weather reports collected during 1992–2021.
All Year Climate & Weather Averages in Janesville
High Temp: 83 °F
Low Temp: 12 °F
Mean Temp: 48 °F
Precipitation: 3.09"
Humidity: 74%
Dew Point: 40 °F
Wind: 15 mph
Pressure: 30.02 "Hg
Visibility: 9 mi
January Climate & Weather Averages in Janesville
High Temp: 29 °F
Low Temp: 12 °F
Mean Temp: 20 °F
Precipitation: 1.70"
Humidity: 80%
Dew Point: 17 °F
Wind: 17 mph
Pressure: 30.08 "Hg
Visibility: 8 mi
February Climate & Weather Averages in Janesville
High Temp: 32 °F
Low Temp: 15 °F
Mean Temp: 23 °F
Precipitation: 1.64"
Humidity: 76%
Dew Point: 19 °F
Wind: 17 mph
Pressure: 30.07 "Hg
Visibility: 9 mi
March Climate & Weather Averages in Janesville
High Temp: 44 °F
Low Temp: 25 °F
Mean Temp: 35 °F
Precipitation: 1.98"
Humidity: 72%
Dew Point: 27 °F
Wind: 17 mph
Pressure: 30.06 "Hg
Visibility: 9 mi
April Climate & Weather Averages in Janesville
High Temp: 58 °F
Low Temp: 35 °F
Mean Temp: 47 °F
Precipitation: 3.53"
Humidity: 66%
Dew Point: 35 °F
Wind: 18 mph
Pressure: 29.96 "Hg
Visibility: 9 mi
May Climate & Weather Averages in Janesville
High Temp: 70 °F
Low Temp: 47 °F
Mean Temp: 58 °F
Precipitation: 4.04"
Humidity: 69%
Dew Point: 47 °F
Wind: 16 mph
Pressure: 29.96 "Hg
Visibility: 10 mi
June Climate & Weather Averages in Janesville
High Temp: 80 °F
Low Temp: 58 °F
Mean Temp: 69 °F
Precipitation: 4.85"
Humidity: 72%
Dew Point: 58 °F
Wind: 13 mph
Pressure: 29.94 "Hg
Visibility: 9 mi
July Climate & Weather Averages in Janesville
High Temp: 83 °F
Low Temp: 62 °F
Mean Temp: 72 °F
Precipitation: 4.21"
Humidity: 76%
Dew Point: 63 °F
Wind: 12 mph
Pressure: 29.98 "Hg
Visibility: 9 mi
August Climate & Weather Averages in Janesville
High Temp: 82 °F
Low Temp: 60 °F
Mean Temp: 71 °F
Precipitation: 4.33"
Humidity: 78%
Dew Point: 62 °F
Wind: 10 mph
Pressure: 30.01 "Hg
Visibility: 9 mi
September Climate & Weather Averages in Janesville
High Temp: 75 °F
Low Temp: 51 °F
Mean Temp: 63 °F
Precipitation: 3.62"
Humidity: 75%
Dew Point: 54 °F
Wind: 12 mph
Pressure: 30.04 "Hg
Visibility: 9 mi
October Climate & Weather Averages in Janesville
High Temp: 62 °F
Low Temp: 39 °F
Mean Temp: 51 °F
Precipitation: 3.03"
Humidity: 74%
Dew Point: 42 °F
Wind: 14 mph
Pressure: 30.03 "Hg
Visibility: 9 mi
November Climate & Weather Averages in Janesville
High Temp: 46 °F
Low Temp: 29 °F
Mean Temp: 38 °F
Precipitation: 2.22"
Humidity: 76%
Dew Point: 30 °F
Wind: 16 mph
Pressure: 30.06 "Hg
Visibility: 9 mi
December Climate & Weather Averages in Janesville
High Temp: 34 °F
Low Temp: 19 °F
Mean Temp: 26 °F
Precipitation: 1.91"
Humidity: 81%
Dew Point: 22 °F
Wind: 16 mph
Pressure: 30.06 "Hg
Visibility: 8 mi