Average annual temperature is 15.1 °C
Absolute maximum temperature: 36.1 °C
Absolute minimum temperature: -11.4 °C
Number of sunny days: 140 days
Number of rainy days: 217 days
Number of snow days: 8 days
Look at detailed online map of Isō
* Weather data for Isō 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) | 15.3 | 15.3 | 23.3 | 24.7 | 28.4 | 30.2 | 35.5 | 36.1 | 33.6 | 26.8 | 25.5 | 19.5 |
| Average daytime temperature (°C) | 7.9 | 8.7 | 15.6 | 17.8 | 22.0 | 25.8 | 31.0 | 32.8 | 29.7 | 21.3 | 16.3 | 11.3 |
| Average temperature (°C) | 2.8 | 4.3 | 9.8 | 12.7 | 17.0 | 21.2 | 26.2 | 27.7 | 25.0 | 16.3 | 11.5 | 6.5 |
| Average night temperature (°C) | -1.4 | 0.6 | 4.9 | 8.6 | 12.9 | 17.6 | 22.8 | 24.3 | 21.7 | 12.3 | 7.9 | 2.8 |
| Absolute minimum temperature (°C) | -11.4 | -4.0 | -2.4 | 0.8 | 6.3 | 11.1 | 19.8 | 22.6 | 16.7 | 6.3 | 0.4 | -3.6 |
| 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) | 6.4 | 6.2 | 8.3 | 7.4 | 9.0 | 6.9 | 9.2 | 10.2 | 9.2 | 8.9 | 7.3 | 6.7 |
| Precipitation (mm) | 57 | 50 | 104 | 238 | 249 | 239 | 104 | 194 | 97 | 61 | 119 | 41 |
| Sunny days | 8 | 7 | 18 | 15 | 17 | 9 | 8 | 1 | 9 | 13 | 17 | 18 |
| Rainy days | 20 | 16 | 13 | 15 | 14 | 21 | 23 | 30 | 21 | 18 | 13 | 13 |
| Snow days | 3 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit Isō during the most sunny months:
The largest precipitation sum in Isō is at