Average annual temperature is 18.3 °C
Absolute maximum temperature: 33.9 °C
Absolute minimum temperature: -2.5 °C
Number of sunny days: 146 days
Number of rainy days: 219 days
Look at detailed online map of Kōyama
* Weather data for Kōyama 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) | 21.6 | 20.0 | 23.4 | 24.0 | 28.6 | 30.8 | 32.6 | 33.9 | 32.7 | 28.5 | 27.2 | 23.8 |
| Average daytime temperature (°C) | 12.4 | 14.4 | 17.8 | 19.8 | 23.1 | 25.9 | 29.9 | 29.4 | 29.4 | 23.7 | 19.6 | 15.0 |
| Average temperature (°C) | 8.4 | 10.8 | 14.1 | 17.0 | 20.1 | 23.3 | 27.2 | 26.8 | 26.3 | 19.4 | 15.2 | 10.8 |
| Average night temperature (°C) | 5.1 | 7.5 | 10.7 | 13.9 | 17.3 | 21.0 | 25.0 | 24.6 | 23.6 | 15.9 | 11.8 | 7.3 |
| Absolute minimum temperature (°C) | -2.5 | 3.3 | 4.5 | 6.7 | 11.0 | 17.6 | 23.0 | 23.2 | 21.2 | 10.9 | 4.6 | -0.6 |
| 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 | 10.0 |
| Daylight mean duration (h) | 10.4 | 11.1 | 12.0 | 12.9 | 13.7 | 14.1 | 14.0 | 13.3 | 12.4 | 11.4 | 10.6 | 10.2 |
| Daylight minimum duration (h) | 10.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 10.0 | 10.0 |
| Sunshine mean duration (h) | 7.5 | 6.9 | 7.7 | 8.0 | 9.0 | 6.0 | 9.7 | 8.4 | 10.5 | 8.3 | 8.4 | 7.3 |
| Precipitation (mm) | 80 | 198 | 255 | 230 | 253 | 517 | 289 | 539 | 50 | 167 | 37 | 121 |
| Sunny days | 21 | 16 | 15 | 11 | 11 | 6 | 0 | 4 | 5 | 20 | 17 | 20 |
| Rainy days | 10 | 12 | 16 | 19 | 20 | 24 | 31 | 27 | 25 | 11 | 13 | 11 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The best time to visit Kōyama during the most sunny months:
The largest precipitation sum in Kōyama is at