Average annual temperature is 9.5 °C
Absolute maximum temperature: 31.4 °C
Absolute minimum temperature: -15.4 °C
Number of sunny days: 114 days
Number of rainy days: 204 days
Number of snow days: 47 days
Look at detailed online map of Iōzan
* Weather data for Iōzan 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) | 7.9 | 7.7 | 15.5 | 18.3 | 23.9 | 25.9 | 30.7 | 31.4 | 27.4 | 21.6 | 19.0 | 11.4 |
| Average daytime temperature (°C) | -2.4 | -0.5 | 7.9 | 11.9 | 16.9 | 21.2 | 25.7 | 27.7 | 23.2 | 16.1 | 9.2 | 1.4 |
| Average temperature (°C) | -5.6 | -3.6 | 3.4 | 7.8 | 12.3 | 17.4 | 22.0 | 24.5 | 20.0 | 12.0 | 5.4 | -2.0 |
| Average night temperature (°C) | -8.3 | -7.0 | 0.1 | 4.6 | 8.6 | 14.5 | 19.0 | 22.1 | 17.4 | 9.1 | 2.3 | -5.0 |
| Absolute minimum temperature (°C) | -15.4 | -13.4 | -6.6 | -1.3 | 2.5 | 9.7 | 14.0 | 18.4 | 11.7 | 2.5 | -5.8 | -12.1 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 9.0 | 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) | 9.5 | 10.6 | 11.9 | 13.4 | 14.6 | 15.2 | 14.9 | 13.8 | 12.5 | 11.1 | 9.8 | 9.2 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 14.0 | 15.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 6.6 | 7.1 | 8.8 | 8.8 | 9.5 | 8.6 | 9.5 | 8.0 | 6.4 | 8.3 | 6.4 | 5.5 |
| Precipitation (mm) | 66 | 43 | 62 | 129 | 53 | 152 | 93 | 154 | 195 | 83 | 139 | 73 |
| Sunny days | 13 | 9 | 16 | 9 | 10 | 9 | 5 | 2 | 7 | 8 | 11 | 15 |
| Rainy days | 2 | 1 | 11 | 20 | 21 | 21 | 26 | 29 | 23 | 23 | 18 | 9 |
| Snow days | 16 | 18 | 4 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 7 |
The largest precipitation sum in Iōzan is at