Average annual temperature is 13.6 °C
Absolute maximum temperature: 33.9 °C
Absolute minimum temperature: -12.4 °C
Number of sunny days: 188 days
Number of rainy days: 173 days
Number of snow days: 4 days
Look at detailed online map of Koyŏn
* Weather data for Koyŏn South Korea is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 15.0 | 12.4 | 22.3 | 23.0 | 23.9 | 28.3 | 31.9 | 33.9 | 30.5 | 23.3 | 24.2 | 17.3 |
| Average daytime temperature (°C) | 5.5 | 8.8 | 14.3 | 16.6 | 19.8 | 24.1 | 27.0 | 29.3 | 26.2 | 20.4 | 13.4 | 8.0 |
| Average temperature (°C) | 1.3 | 3.9 | 9.4 | 12.3 | 16.1 | 20.5 | 23.9 | 25.7 | 22.1 | 15.3 | 8.4 | 3.4 |
| Average night temperature (°C) | -2.9 | -0.1 | 5.3 | 8.5 | 13.1 | 17.7 | 21.4 | 22.9 | 18.9 | 10.8 | 4.3 | -0.3 |
| Absolute minimum temperature (°C) | -12.4 | -5.4 | -2.1 | 2.0 | 6.9 | 14.7 | 17.9 | 20.8 | 14.6 | 5.5 | -4.3 | -9.9 |
| 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 | 9.0 |
| Daylight mean duration (h) | 10.1 | 10.9 | 12.0 | 13.1 | 14.0 | 14.5 | 14.2 | 13.4 | 12.4 | 11.3 | 10.3 | 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) | 7.7 | 7.5 | 8.7 | 7.7 | 7.6 | 8.3 | 6.7 | 9.7 | 7.6 | 8.8 | 8.2 | 7.2 |
| Precipitation (mm) | 54 | 41 | 75 | 134 | 231 | 231 | 374 | 317 | 258 | 12 | 41 | 77 |
| Sunny days | 25 | 20 | 20 | 14 | 13 | 8 | 4 | 6 | 11 | 24 | 23 | 20 |
| Rainy days | 5 | 8 | 11 | 16 | 18 | 22 | 27 | 25 | 19 | 7 | 7 | 8 |
| Snow days | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 |
The largest precipitation sum in Koyŏn is at