Average annual temperature is 12.0 °C
Absolute maximum temperature: 32.8 °C
Absolute minimum temperature: -16.4 °C
Number of sunny days: 163 days
Number of rainy days: 188 days
Number of snow days: 14 days
Look at detailed online map of Osan
* Weather data for Osan 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) | 14.5 | 11.6 | 21.0 | 23.5 | 28.9 | 31.0 | 31.6 | 32.8 | 29.1 | 20.9 | 22.2 | 16.8 |
| Average daytime temperature (°C) | 2.6 | 6.2 | 14.2 | 16.7 | 21.3 | 25.9 | 27.4 | 29.0 | 25.2 | 18.3 | 10.3 | 4.9 |
| Average temperature (°C) | -1.8 | 0.7 | 7.7 | 11.0 | 16.2 | 20.5 | 23.7 | 24.6 | 20.8 | 12.9 | 5.6 | 1.1 |
| Average night temperature (°C) | -5.7 | -3.1 | 2.8 | 6.0 | 11.7 | 16.4 | 20.9 | 21.2 | 17.5 | 8.3 | 1.3 | -2.3 |
| Absolute minimum temperature (°C) | -16.4 | -8.0 | -4.8 | -1.0 | 4.0 | 12.9 | 18.0 | 17.2 | 11.1 | 3.7 | -8.3 | -13.4 |
| 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 | 14.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 10.0 | 10.9 | 12.0 | 13.1 | 14.1 | 14.5 | 14.3 | 13.5 | 12.4 | 11.3 | 10.3 | 9.8 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 13.0 | 12.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 7.0 | 7.4 | 9.0 | 7.5 | 8.2 | 9.3 | 6.8 | 9.3 | 7.5 | 8.7 | 7.1 | 5.8 |
| Precipitation (mm) | 46 | 13 | 51 | 88 | 154 | 175 | 569 | 318 | 164 | 13 | 90 | 127 |
| Sunny days | 15 | 20 | 23 | 13 | 14 | 10 | 2 | 4 | 8 | 24 | 16 | 14 |
| Rainy days | 8 | 6 | 8 | 17 | 17 | 20 | 29 | 27 | 22 | 7 | 14 | 13 |
| Snow days | 8 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 4 |
The largest precipitation sum in Osan is at