Average annual temperature is 17.0 °C
Absolute maximum temperature: 35.0 °C
Absolute minimum temperature: -3.9 °C
Number of sunny days: 150 days
Number of rainy days: 214 days
Number of snow days: 1 day
Look at detailed online map of Isumi-gun
* Weather data for Isumi-gun Japan is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 16.3 | 18.9 | 25.3 | 25.8 | 30.6 | 31.5 | 34.5 | 35.0 | 33.0 | 31.3 | 25.2 | 23.0 |
| Average daytime temperature (°C) | 10.1 | 11.4 | 16.7 | 19.8 | 22.0 | 26.3 | 31.6 | 31.9 | 29.7 | 23.0 | 19.1 | 14.4 |
| Average temperature (°C) | 5.5 | 7.2 | 12.4 | 15.7 | 18.1 | 22.3 | 26.8 | 27.6 | 25.9 | 18.2 | 14.8 | 9.4 |
| Average night temperature (°C) | 1.8 | 3.3 | 8.9 | 12.5 | 15.0 | 19.5 | 23.5 | 24.8 | 23.3 | 14.2 | 11.4 | 5.3 |
| Absolute minimum temperature (°C) | -3.9 | -2.8 | 1.2 | 5.7 | 9.9 | 15.9 | 20.9 | 22.9 | 18.8 | 10.5 | 5.1 | -0.9 |
| 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) | 6.5 | 7.0 | 7.6 | 8.8 | 8.3 | 7.2 | 10.8 | 11.5 | 9.1 | 8.9 | 7.2 | 7.4 |
| Precipitation (mm) | 58 | 99 | 171 | 186 | 149 | 258 | 41 | 112 | 206 | 141 | 79 | 43 |
| Sunny days | 18 | 15 | 8 | 12 | 11 | 6 | 18 | 4 | 5 | 16 | 17 | 20 |
| Rainy days | 12 | 13 | 23 | 18 | 20 | 24 | 13 | 27 | 25 | 15 | 13 | 11 |
| Snow days | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit Isumi-gun during the most sunny months:
The largest precipitation sum in Isumi-gun is at