Average annual temperature is 13.4 °C
Absolute maximum temperature: 32.9 °C
Absolute minimum temperature: -9.8 °C
Number of sunny days: 152 days
Number of rainy days: 205 days
Number of snow days: 8 days
Look at detailed online map of Kōyamaichi
* Weather data for Kōyamaichi 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) | 14.3 | 14.0 | 19.9 | 23.4 | 27.1 | 28.0 | 31.9 | 32.9 | 30.7 | 24.1 | 23.5 | 17.5 |
| Average daytime temperature (°C) | 6.1 | 7.4 | 14.3 | 16.6 | 20.7 | 23.9 | 28.2 | 29.2 | 27.3 | 19.5 | 14.2 | 8.4 |
| Average temperature (°C) | 1.8 | 2.9 | 8.8 | 11.4 | 15.7 | 19.6 | 24.1 | 24.9 | 22.6 | 14.5 | 9.7 | 4.4 |
| Average night temperature (°C) | -1.3 | -0.6 | 4.5 | 7.3 | 11.8 | 16.4 | 20.8 | 21.7 | 19.5 | 10.8 | 6.2 | 1.4 |
| Absolute minimum temperature (°C) | -9.8 | -5.5 | -3.3 | 1.6 | 6.5 | 11.3 | 17.3 | 19.9 | 16.3 | 6.6 | 0.0 | -5.3 |
| 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 | 10.0 |
| Daylight mean duration (h) | 10.1 | 10.9 | 12.0 | 13.1 | 14.0 | 14.4 | 14.2 | 13.4 | 12.4 | 11.3 | 10.4 | 9.9 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 10.0 | 9.0 |
| Sunshine mean duration (h) | 6.7 | 6.2 | 8.2 | 7.8 | 8.8 | 7.3 | 9.4 | 9.8 | 9.1 | 8.6 | 7.8 | 6.7 |
| Precipitation (mm) | 33 | 50 | 81 | 197 | 244 | 225 | 136 | 152 | 47 | 26 | 39 | 61 |
| Sunny days | 16 | 14 | 17 | 17 | 14 | 9 | 7 | 4 | 5 | 18 | 17 | 14 |
| Rainy days | 10 | 13 | 14 | 13 | 17 | 21 | 24 | 27 | 25 | 13 | 13 | 15 |
| Snow days | 5 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 |
The largest precipitation sum in Kōyamaichi is at