Average annual temperature is 12.6 °C
Absolute maximum temperature: 36.1 °C
Absolute minimum temperature: -10.0 °C
Number of sunny days: 70 days
Number of rainy days: 255 days
Number of snow days: 40 days
Look at detailed online map of Koikawa
* Weather data for Koikawa 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) | 11.3 | 10.8 | 21.2 | 20.1 | 23.8 | 28.3 | 31.0 | 36.1 | 32.9 | 22.9 | 23.7 | 13.3 |
| Average daytime temperature (°C) | 1.7 | 2.2 | 11.2 | 14.1 | 18.6 | 23.8 | 27.0 | 32.7 | 27.0 | 18.5 | 12.4 | 4.7 |
| Average temperature (°C) | -0.8 | -0.1 | 6.5 | 10.2 | 14.2 | 20.2 | 23.9 | 28.3 | 22.6 | 14.2 | 9.3 | 2.1 |
| Average night temperature (°C) | -3.5 | -2.8 | 2.3 | 6.8 | 10.4 | 17.1 | 21.2 | 24.7 | 19.3 | 10.7 | 6.3 | -0.7 |
| Absolute minimum temperature (°C) | -10.0 | -7.8 | -4.3 | 0.8 | 3.3 | 12.7 | 16.2 | 23.0 | 10.9 | 4.8 | -1.4 | -8.4 |
| 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 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 9.7 | 10.7 | 12.0 | 13.3 | 14.4 | 15.0 | 14.7 | 13.7 | 12.5 | 11.1 | 10.0 | 9.4 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 5.5 | 6.0 | 8.2 | 8.6 | 9.0 | 8.2 | 8.6 | 11.8 | 7.9 | 7.8 | 5.2 | 3.9 |
| Precipitation (mm) | 120 | 79 | 89 | 154 | 187 | 209 | 445 | 79 | 238 | 231 | 264 | 133 |
| Sunny days | 1 | 4 | 15 | 10 | 8 | 5 | 3 | 7 | 6 | 7 | 3 | 1 |
| Rainy days | 11 | 14 | 16 | 20 | 23 | 25 | 28 | 24 | 24 | 24 | 26 | 20 |
| Snow days | 19 | 10 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 10 |
The best time to visit Koikawa during the most sunny months:
The largest precipitation sum in Koikawa is at