Average annual temperature is 10.8 °C
Absolute maximum temperature: 37.7 °C
Absolute minimum temperature: -25.3 °C
Number of sunny days: 204 days
Number of rainy days: 137 days
Number of snow days: 24 days
Look at detailed online map of Grundy County
* Weather data for Grundy County United States is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 10.6 | 11.2 | 21.8 | 26.2 | 30.5 | 31.0 | 33.4 | 37.7 | 34.0 | 31.0 | 17.5 | 13.1 |
| Average daytime temperature (°C) | 0.1 | 3.1 | 6.7 | 16.0 | 24.0 | 28.0 | 27.9 | 28.3 | 26.2 | 17.0 | 9.9 | 5.8 |
| Average temperature (°C) | -4.1 | -2.5 | 1.0 | 9.6 | 17.5 | 22.3 | 22.7 | 23.2 | 20.3 | 12.4 | 4.7 | 1.6 |
| Average night temperature (°C) | -7.1 | -6.9 | -3.2 | 4.2 | 11.5 | 16.9 | 17.5 | 18.6 | 15.5 | 8.4 | 0.8 | -1.1 |
| Absolute minimum temperature (°C) | -25.3 | -25.3 | -16.5 | -4.6 | 1.2 | 9.0 | 11.6 | 12.4 | 9.6 | -4.8 | -13.2 | -7.2 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 9.0 | 11.0 | 12.0 | 14.0 | 15.0 | 15.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 9.5 | 10.6 | 11.9 | 13.4 | 14.6 | 15.2 | 14.9 | 13.9 | 12.5 | 11.1 | 9.8 | 9.1 |
| Daylight minimum duration (h) | 9.0 | 9.0 | 11.0 | 12.0 | 14.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 4.4 | 7.0 | 7.3 | 9.4 | 11.8 | 11.9 | 12.4 | 11.4 | 10.1 | 7.2 | 7.1 | 4.2 |
| Precipitation (mm) | 66 | 45 | 67 | 39 | 93 | 41 | 92 | 62 | 38 | 79 | 11 | 41 |
| Sunny days | 17 | 18 | 15 | 17 | 19 | 16 | 14 | 17 | 17 | 16 | 21 | 17 |
| Rainy days | 6 | 9 | 9 | 12 | 12 | 14 | 17 | 14 | 13 | 14 | 8 | 9 |
| Snow days | 8 | 1 | 7 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 5 |
The best time to visit Grundy County during the most sunny months:
The largest precipitation sum in Grundy County is at