Janesville, WI
Climate overview — based on NOAA 1991-2020 normals from AFTON - JANESVILLE WWTP, WI US.
Year-round temperatures (°F)
Climate summary
Janesville has an annual average temperature of 47.8°F with about 37.4 inches of precipitation per year and 36.6 inches of snow. The warmest month is July (average high 83.4°F), and the coldest is January (average low 11.6°F). June is typically the wettest month (4.99 in) and February the driest (1.61 in). Snow typically falls from October through April.
Best time to visit Janesville
Full guide →Climate change signal
All-time records →113 of 366 (30.9%) of Janesville's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.
| 1980s | 34 | |
| 1990s | 81 | |
| 2000s | 76 | |
| 2010s | 107 | |
| 2020s | 68 |
Bars: number of all-time daily heat records still standing that were set in each decade.
Monthly averages
| Month | Avg High | Avg Low | Avg Temp | Precipitation | Snow | Rainy days |
|---|---|---|---|---|---|---|
| January | 28.3°F | 11.6°F | 19.9°F | 1.63 in | 10.8 in | 10 |
| February | 32.4°F | 14.7°F | 23.5°F | 1.61 in | 10.1 in | 9 |
| March | 44.6°F | 25.4°F | 35.0°F | 2.06 in | 4.1 in | 10 |
| April | 57.9°F | 36.1°F | 47.0°F | 3.57 in | 1.3 in | 12 |
| May | 69.9°F | 48.0°F | 58.9°F | 4.09 in | — | 13 |
| June | 79.9°F | 58.0°F | 68.9°F | 4.99 in | — | 13 |
| July | 83.4°F | 61.7°F | 72.6°F | 4.19 in | — | 10 |
| August | 81.7°F | 59.5°F | 70.6°F | 4.34 in | — | 10 |
| September | 75.1°F | 51.0°F | 63.0°F | 3.73 in | — | 10 |
| October | 61.7°F | 39.5°F | 50.6°F | 2.99 in | 0.2 in | 10 |
| November | 46.3°F | 28.5°F | 37.4°F | 2.33 in | 2.4 in | 9 |
| December | 33.5°F | 18.1°F | 25.8°F | 1.90 in | 7.7 in | 10 |
Climate twins of Janesville
Why these? →The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).