Average annual temperature is 10.5 °C
Absolute maximum temperature: 31.2 °C
Absolute minimum temperature: -13.6 °C
Number of sunny days: 115 days
Number of rainy days: 202 days
Number of snow days: 48 days
Look at detailed online map of Iwatochō
* Weather data for Iwatochō 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) | 8.5 | 8.5 | 14.6 | 17.4 | 24.3 | 25.9 | 31.2 | 31.1 | 28.1 | 22.8 | 20.6 | 12.8 |
| Average daytime temperature (°C) | -1.5 | 0.2 | 8.2 | 12.4 | 17.3 | 21.3 | 26.1 | 28.0 | 23.9 | 17.0 | 10.2 | 2.4 |
| Average temperature (°C) | -4.2 | -2.3 | 4.1 | 8.6 | 13.1 | 18.0 | 22.9 | 25.2 | 21.1 | 13.1 | 6.7 | -0.5 |
| Average night temperature (°C) | -6.5 | -5.2 | 1.1 | 5.8 | 9.7 | 15.4 | 20.2 | 23.1 | 18.7 | 10.4 | 3.7 | -2.9 |
| Absolute minimum temperature (°C) | -13.6 | -10.0 | -5.3 | 0.5 | 4.2 | 10.8 | 15.7 | 19.4 | 13.3 | 4.2 | -4.3 | -8.0 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 9.0 | 11.0 | 12.0 | 13.0 | 15.0 | 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 | 6.9 | 8.8 | 8.7 | 9.5 | 8.8 | 9.7 | 8.4 | 6.6 | 8.3 | 6.4 | 5.3 |
| Precipitation (mm) | 71 | 52 | 58 | 115 | 50 | 127 | 92 | 130 | 166 | 104 | 121 | 70 |
| Sunny days | 15 | 5 | 17 | 10 | 10 | 10 | 6 | 1 | 8 | 9 | 11 | 13 |
| Rainy days | 2 | 4 | 10 | 20 | 21 | 20 | 25 | 30 | 22 | 22 | 16 | 10 |
| Snow days | 14 | 19 | 4 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 8 |
The largest precipitation sum in Iwatochō is at