Average annual temperature is 22.3 °C
Absolute maximum temperature: 29.5 °C
Absolute minimum temperature: 16.5 °C
Number of sunny days: 24 days
Number of rainy days: 341 days
Look at detailed online map of Siantar
* Weather data for Siantar Indonesia is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 26.2 | 26.9 | 27.1 | 27.9 | 29.0 | 29.5 | 29.2 | 28.7 | 28.4 | 28.8 | 27.6 | 28.0 |
| Average daytime temperature (°C) | 24.6 | 25.4 | 25.3 | 26.0 | 27.1 | 27.5 | 27.2 | 26.7 | 26.6 | 26.3 | 25.8 | 25.5 |
| Average temperature (°C) | 21.1 | 21.4 | 21.5 | 22.1 | 22.8 | 22.9 | 22.7 | 22.5 | 22.8 | 22.6 | 22.4 | 22.4 |
| Average night temperature (°C) | 18.3 | 18.3 | 18.9 | 19.2 | 19.7 | 19.3 | 19.5 | 19.5 | 19.9 | 19.7 | 19.8 | 19.9 |
| Absolute minimum temperature (°C) | 16.5 | 17.4 | 17.2 | 17.9 | 18.4 | 17.8 | 17.9 | 18.5 | 18.8 | 18.4 | 18.7 | 18.3 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 11.0 |
| Daylight mean duration (h) | 12.0 | 12.0 | 12.1 | 12.2 | 12.2 | 12.3 | 12.3 | 12.2 | 12.1 | 12.1 | 12.0 | 12.0 |
| Daylight minimum duration (h) | 11.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 11.0 | 11.0 |
| Sunshine mean duration (h) | 8.3 | 9.0 | 8.7 | 8.3 | 8.8 | 9.2 | 8.4 | 7.6 | 7.8 | 7.8 | 6.7 | 8.2 |
| Precipitation (mm) | 245 | 189 | 186 | 222 | 165 | 216 | 99 | 300 | 252 | 282 | 403 | 354 |
| Sunny days | 1 | 1 | 0 | 0 | 2 | 8 | 11 | 1 | 0 | 0 | 0 | 0 |
| Rainy days | 30 | 27 | 31 | 30 | 29 | 22 | 20 | 30 | 30 | 31 | 30 | 31 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The largest precipitation sum in Siantar is at