Average annual temperature is 11.5 °C
Absolute maximum temperature: 36.0 °C
Absolute minimum temperature: -20.9 °C
Number of sunny days: 227 days
Number of rainy days: 118 days
Number of snow days: 20 days
Look at detailed online map of Portsmouth
* Weather data for Portsmouth 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) | 8.2 | 12.7 | 19.6 | 28.6 | 29.6 | 31.9 | 34.7 | 36.0 | 33.7 | 31.5 | 18.0 | 14.0 |
| Average daytime temperature (°C) | 0.5 | 4.7 | 7.8 | 17.9 | 24.9 | 29.3 | 28.7 | 28.7 | 26.7 | 17.7 | 11.0 | 6.1 |
| Average temperature (°C) | -3.6 | -1.7 | 1.5 | 10.6 | 18.5 | 23.4 | 23.2 | 23.7 | 21.1 | 12.7 | 5.5 | 1.7 |
| Average night temperature (°C) | -6.8 | -6.1 | -2.9 | 5.1 | 12.7 | 17.6 | 18.3 | 19.3 | 16.2 | 8.6 | 1.0 | -1.7 |
| Absolute minimum temperature (°C) | -20.9 | -20.8 | -12.8 | -5.0 | 2.2 | 9.2 | 10.9 | 12.4 | 10.9 | -5.8 | -8.6 | -5.2 |
| 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 | 15.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 9.6 | 10.6 | 11.9 | 13.3 | 14.5 | 15.1 | 14.9 | 13.8 | 12.5 | 11.1 | 9.9 | 9.2 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 14.0 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 4.6 | 7.3 | 8.0 | 9.5 | 11.7 | 12.9 | 11.5 | 11.4 | 10.2 | 7.7 | 6.9 | 4.9 |
| Precipitation (mm) | 53 | 68 | 39 | 32 | 62 | 46 | 86 | 75 | 40 | 56 | 6 | 47 |
| Sunny days | 18 | 18 | 20 | 18 | 18 | 17 | 15 | 18 | 22 | 16 | 24 | 23 |
| Rainy days | 7 | 7 | 8 | 10 | 13 | 13 | 16 | 13 | 8 | 14 | 5 | 4 |
| Snow days | 6 | 3 | 3 | 2 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 4 |
The best time to visit Portsmouth during the most sunny months:
The largest precipitation sum in Portsmouth is at