Average annual temperature is 13.8 °C
Absolute maximum temperature: 36.3 °C
Absolute minimum temperature: -7.7 °C
Number of sunny days: 206 days
Number of rainy days: 156 days
Number of snow days: 3 days
Look at detailed online map of Cornwall
* Weather data for Cornwall 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) | 18.1 | 23.8 | 25.4 | 29.9 | 29.7 | 31.7 | 36.3 | 34.6 | 35.2 | 28.5 | 25.5 | 18.6 |
| Average daytime temperature (°C) | 10.2 | 13.5 | 14.5 | 21.8 | 23.3 | 26.9 | 32.3 | 30.6 | 26.9 | 21.2 | 14.2 | 10.7 |
| Average temperature (°C) | 4.7 | 7.1 | 7.5 | 13.8 | 16.6 | 20.0 | 25.1 | 23.8 | 20.2 | 14.2 | 7.0 | 4.7 |
| Average night temperature (°C) | 0.4 | 2.0 | 1.6 | 6.5 | 10.5 | 13.3 | 18.6 | 17.9 | 14.5 | 8.6 | 1.5 | 0.6 |
| Absolute minimum temperature (°C) | -5.0 | -7.7 | -6.0 | -1.2 | 1.9 | 8.4 | 15.7 | 12.5 | 9.7 | 0.9 | -5.9 | -5.0 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 14.0 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 9.9 | 10.8 | 12.0 | 13.2 | 14.2 | 14.7 | 14.5 | 13.6 | 12.4 | 11.2 | 10.2 | 9.6 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 5.7 | 7.3 | 8.2 | 9.7 | 10.4 | 10.7 | 12.4 | 10.9 | 9.6 | 9.1 | 8.1 | 6.1 |
| Precipitation (mm) | 59 | 69 | 41 | 108 | 55 | 78 | 66 | 35 | 42 | 23 | 52 | 95 |
| Sunny days | 13 | 14 | 17 | 20 | 15 | 14 | 13 | 16 | 16 | 23 | 25 | 20 |
| Rainy days | 17 | 13 | 13 | 10 | 16 | 16 | 18 | 15 | 14 | 8 | 5 | 11 |
| Snow days | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit Cornwall during the most sunny months:
The largest precipitation sum in Cornwall is at