Average annual temperature is 9.8 °C
Absolute maximum temperature: 32.0 °C
Absolute minimum temperature: -27.3 °C
Number of sunny days: 117 days
Number of rainy days: 226 days
Number of snow days: 22 days
Look at detailed online map of Jefferson County
* Weather data for Jefferson 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) | 8.3 | 15.2 | 9.5 | 25.6 | 26.2 | 29.8 | 32.0 | 28.3 | 28.4 | 27.8 | 14.7 | 12.0 |
| Average daytime temperature (°C) | 2.1 | 3.3 | 4.0 | 14.0 | 17.2 | 23.2 | 25.8 | 23.5 | 22.4 | 16.0 | 7.7 | 6.0 |
| Average temperature (°C) | -0.8 | -2.0 | 0.5 | 8.7 | 12.2 | 18.3 | 21.9 | 19.9 | 18.1 | 12.6 | 4.1 | 2.9 |
| Average night temperature (°C) | -3.5 | -6.3 | -2.8 | 4.4 | 7.5 | 14.2 | 18.6 | 16.8 | 14.6 | 10.1 | 1.3 | 0.4 |
| Absolute minimum temperature (°C) | -11.4 | -27.3 | -10.4 | -6.1 | 2.8 | 8.7 | 15.7 | 12.3 | 8.6 | 0.5 | -4.3 | -8.3 |
| 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) | 9.3 | 10.5 | 11.9 | 13.5 | 14.7 | 15.4 | 15.1 | 14.0 | 12.5 | 11.0 | 9.7 | 9.0 |
| Daylight minimum duration (h) | 8.0 | 9.0 | 11.0 | 12.0 | 14.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 8.0 |
| Sunshine mean duration (h) | 2.7 | 5.2 | 5.7 | 8.8 | 12.0 | 11.1 | 11.8 | 10.4 | 9.9 | 5.4 | 4.9 | 2.9 |
| Precipitation (mm) | 131 | 99 | 85 | 95 | 82 | 143 | 152 | 165 | 39 | 159 | 90 | 153 |
| Sunny days | 5 | 4 | 11 | 13 | 17 | 9 | 12 | 4 | 18 | 9 | 7 | 8 |
| Rainy days | 21 | 17 | 15 | 17 | 14 | 21 | 19 | 27 | 12 | 22 | 20 | 21 |
| Snow days | 5 | 7 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 2 |
The best time to visit Jefferson County during the most sunny months:
Months with the longest average daylight duration in Jefferson County:
The largest precipitation sum in Jefferson County is at