Average annual temperature is 17.4 °C
Absolute maximum temperature: 37.2 °C
Absolute minimum temperature: -4.8 °C
Number of sunny days: 196 days
Number of rainy days: 169 days
Look at detailed online map of Grantham
* Weather data for Grantham 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) | 22.3 | 26.9 | 28.5 | 29.7 | 30.5 | 32.2 | 34.8 | 37.2 | 34.6 | 27.9 | 25.0 | 22.8 |
| Average daytime temperature (°C) | 15.0 | 17.3 | 18.6 | 23.6 | 24.7 | 29.0 | 32.3 | 32.6 | 28.1 | 22.9 | 16.8 | 14.6 |
| Average temperature (°C) | 9.8 | 11.9 | 12.7 | 17.3 | 19.4 | 23.3 | 26.9 | 27.0 | 22.5 | 17.3 | 11.3 | 9.1 |
| Average night temperature (°C) | 5.7 | 7.9 | 7.9 | 12.0 | 14.4 | 18.1 | 22.6 | 22.4 | 17.9 | 12.7 | 7.0 | 5.0 |
| Absolute minimum temperature (°C) | -1.6 | -4.8 | -2.3 | 1.6 | 8.2 | 12.2 | 19.8 | 18.6 | 12.7 | 5.6 | -3.5 | -2.0 |
| 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 | 13.0 | 12.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 10.1 | 10.9 | 12.0 | 13.1 | 14.0 | 14.5 | 14.3 | 13.5 | 12.4 | 11.3 | 10.3 | 9.8 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 6.7 | 6.9 | 8.3 | 9.2 | 10.0 | 11.6 | 11.5 | 11.0 | 9.8 | 9.0 | 7.5 | 6.7 |
| Precipitation (mm) | 106 | 81 | 65 | 159 | 76 | 99 | 104 | 145 | 118 | 25 | 57 | 133 |
| Sunny days | 19 | 10 | 19 | 14 | 18 | 12 | 9 | 15 | 18 | 23 | 20 | 19 |
| Rainy days | 12 | 18 | 12 | 16 | 13 | 18 | 22 | 16 | 12 | 8 | 10 | 12 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit Grantham during the most sunny months:
The largest precipitation sum in Grantham is at