Average annual temperature is 14.7 °C
Absolute maximum temperature: 32.8 °C
Absolute minimum temperature: -12.5 °C
Number of sunny days: 205 days
Number of rainy days: 158 days
Number of snow days: 2 days
Look at detailed online map of Ilsan
* Weather data for Ilsan 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) | 16.8 | 14.9 | 23.8 | 26.4 | 27.7 | 29.4 | 31.7 | 32.8 | 28.6 | 24.2 | 26.6 | 20.3 |
| Average daytime temperature (°C) | 6.9 | 10.0 | 15.9 | 18.2 | 21.1 | 25.3 | 28.3 | 29.3 | 26.2 | 21.5 | 14.9 | 9.2 |
| Average temperature (°C) | 1.9 | 5.0 | 10.6 | 13.9 | 17.4 | 21.9 | 25.4 | 26.5 | 23.3 | 16.0 | 9.2 | 4.4 |
| Average night temperature (°C) | -2.2 | 0.6 | 5.5 | 9.5 | 13.6 | 18.8 | 22.6 | 23.9 | 20.7 | 11.2 | 4.0 | 0.2 |
| Absolute minimum temperature (°C) | -12.5 | -4.4 | -1.3 | 3.2 | 5.6 | 15.3 | 18.2 | 21.9 | 15.2 | 5.2 | -3.8 | -9.1 |
| 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 | 14.3 | 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) | 7.8 | 7.4 | 9.1 | 8.6 | 8.1 | 8.9 | 8.5 | 9.7 | 7.8 | 8.8 | 8.0 | 7.1 |
| Precipitation (mm) | 62 | 44 | 60 | 75 | 208 | 150 | 219 | 238 | 168 | 4 | 36 | 102 |
| Sunny days | 24 | 18 | 21 | 18 | 18 | 14 | 9 | 7 | 5 | 24 | 24 | 23 |
| Rainy days | 5 | 10 | 10 | 12 | 13 | 16 | 22 | 24 | 25 | 7 | 6 | 8 |
| Snow days | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The largest precipitation sum in Ilsan is at