Average annual temperature is 10.9 °C
Absolute maximum temperature: 36.4 °C
Absolute minimum temperature: -24.3 °C
Number of sunny days: 178 days
Number of rainy days: 167 days
Number of snow days: 20 days
Look at detailed online map of St. Charles
* Weather data for St. Charles 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) | 9.6 | 14.5 | 19.9 | 25.4 | 31.8 | 32.8 | 33.3 | 36.4 | 33.4 | 27.1 | 19.3 | 14.1 |
| Average daytime temperature (°C) | 2.5 | 4.9 | 7.6 | 16.1 | 22.4 | 27.8 | 28.4 | 27.6 | 24.2 | 16.4 | 9.3 | 6.2 |
| Average temperature (°C) | -1.1 | -0.5 | 2.4 | 9.4 | 15.8 | 21.0 | 22.8 | 22.2 | 19.1 | 12.2 | 4.5 | 2.7 |
| Average night temperature (°C) | -3.8 | -4.5 | -1.2 | 3.9 | 10.1 | 15.2 | 17.9 | 17.6 | 15.1 | 8.7 | 0.7 | 0.4 |
| Absolute minimum temperature (°C) | -24.3 | -21.2 | -12.0 | -2.5 | 0.9 | 7.8 | 14.0 | 12.1 | 9.2 | -3.2 | -11.3 | -8.1 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 9.0 | 11.0 | 12.0 | 13.0 | 14.0 | 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 | 13.8 | 12.5 | 11.1 | 9.8 | 9.2 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 14.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 3.5 | 7.7 | 6.4 | 9.0 | 10.7 | 11.9 | 11.7 | 10.4 | 8.0 | 6.5 | 7.1 | 3.8 |
| Precipitation (mm) | 60 | 88 | 88 | 81 | 63 | 31 | 197 | 95 | 135 | 98 | 35 | 74 |
| Sunny days | 12 | 16 | 11 | 14 | 20 | 18 | 12 | 15 | 10 | 13 | 22 | 15 |
| Rainy days | 11 | 9 | 15 | 16 | 11 | 12 | 19 | 16 | 20 | 17 | 7 | 14 |
| Snow days | 8 | 3 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 2 |
The best time to visit St. Charles during the most sunny months:
The largest precipitation sum in St. Charles is at