Average annual temperature is 14.8 °C
Absolute maximum temperature: 37.2 °C
Absolute minimum temperature: -9.5 °C
Number of sunny days: 196 days
Number of rainy days: 167 days
Number of snow days: 2 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) | 19.7 | 21.1 | 23.6 | 27.6 | 31.3 | 36.0 | 35.7 | 37.2 | 32.5 | 29.7 | 25.5 | 18.1 |
| Average daytime temperature (°C) | 9.2 | 12.4 | 13.7 | 20.4 | 25.9 | 30.6 | 31.6 | 30.1 | 27.6 | 20.9 | 14.9 | 10.8 |
| Average temperature (°C) | 4.3 | 6.2 | 7.6 | 13.8 | 19.5 | 23.9 | 25.5 | 24.6 | 21.5 | 15.4 | 8.9 | 6.0 |
| Average night temperature (°C) | 1.0 | 1.8 | 3.0 | 8.4 | 14.2 | 17.7 | 20.8 | 20.4 | 16.6 | 11.1 | 4.5 | 2.8 |
| Absolute minimum temperature (°C) | -9.5 | -8.8 | -6.9 | 1.1 | 6.5 | 12.6 | 16.0 | 14.2 | 12.5 | -3.6 | -4.6 | -5.7 |
| 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 | 12.0 | 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 | 7.5 | 10.4 | 11.0 | 13.0 | 11.6 | 9.9 | 10.4 | 7.6 | 7.9 | 6.4 |
| Precipitation (mm) | 118 | 68 | 211 | 70 | 44 | 34 | 100 | 127 | 42 | 56 | 16 | 48 |
| Sunny days | 13 | 17 | 13 | 16 | 17 | 18 | 10 | 17 | 16 | 18 | 24 | 17 |
| Rainy days | 17 | 10 | 18 | 14 | 14 | 12 | 21 | 14 | 14 | 13 | 6 | 14 |
| Snow days | 1 | 1 | 0 | 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