Average annual temperature is 11.1 °C
Absolute maximum temperature: 33.3 °C
Absolute minimum temperature: -20.7 °C
Number of sunny days: 166 days
Number of rainy days: 175 days
Number of snow days: 24 days
Look at detailed online map of Siyŏul
* Weather data for Siyŏul 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) | 11.9 | 11.3 | 21.7 | 24.8 | 28.2 | 31.0 | 33.2 | 33.3 | 29.7 | 20.6 | 21.6 | 14.0 |
| Average daytime temperature (°C) | 0.8 | 5.3 | 13.3 | 16.0 | 21.7 | 25.8 | 29.3 | 29.0 | 25.0 | 17.7 | 8.7 | 2.6 |
| Average temperature (°C) | -3.7 | 0.1 | 6.4 | 10.1 | 16.1 | 20.4 | 24.7 | 24.4 | 20.3 | 11.9 | 3.9 | -1.5 |
| Average night temperature (°C) | -7.8 | -3.3 | 1.0 | 5.2 | 10.9 | 15.9 | 21.2 | 20.9 | 16.7 | 7.3 | 0.0 | -4.9 |
| Absolute minimum temperature (°C) | -20.7 | -6.9 | -6.3 | -1.8 | 2.3 | 12.4 | 18.2 | 15.2 | 10.5 | 1.4 | -9.6 | -17.0 |
| 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 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 |
| Daylight mean duration (h) | 9.9 | 10.8 | 12.0 | 13.2 | 14.2 | 14.8 | 14.5 | 13.6 | 12.4 | 11.2 | 10.1 | 9.6 |
| Daylight minimum duration (h) | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 14.0 | 13.0 | 11.0 | 10.0 | 9.0 | 9.0 |
| Sunshine mean duration (h) | 6.9 | 8.0 | 9.1 | 7.5 | 9.4 | 9.7 | 8.2 | 8.4 | 7.4 | 8.1 | 6.5 | 5.9 |
| Precipitation (mm) | 39 | 2 | 19 | 109 | 109 | 211 | 290 | 283 | 124 | 18 | 92 | 82 |
| Sunny days | 18 | 19 | 21 | 14 | 19 | 7 | 3 | 5 | 9 | 17 | 16 | 18 |
| Rainy days | 3 | 1 | 10 | 16 | 12 | 23 | 28 | 26 | 21 | 14 | 12 | 9 |
| Snow days | 10 | 8 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 4 |
The largest precipitation sum in Siyŏul is at