Average annual temperature is 26.1 °C
Absolute maximum temperature: 33.5 °C
Absolute minimum temperature: 19.6 °C
Number of sunny days: 21 days
Number of rainy days: 344 days
Look at detailed online map of Heiyanthuduwa West
* Weather data for Heiyanthuduwa West Sri Lanka is based on climate observations for 2026 year
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute maximum temperature (°C) | 31.5 | 33.5 | 33.0 | 33.3 | 31.5 | 30.5 | 30.2 | 30.7 | 30.5 | 31.3 | 31.5 | 32.4 |
| Average daytime temperature (°C) | 30.2 | 30.8 | 31.2 | 31.8 | 30.1 | 29.5 | 29.3 | 29.8 | 28.7 | 29.4 | 30.0 | 30.3 |
| Average temperature (°C) | 25.2 | 25.6 | 26.3 | 26.9 | 26.9 | 26.5 | 26.6 | 26.7 | 25.5 | 25.4 | 25.3 | 25.8 |
| Average night temperature (°C) | 21.3 | 21.6 | 22.7 | 23.2 | 24.4 | 24.0 | 24.2 | 24.1 | 23.5 | 22.8 | 22.6 | 22.9 |
| Absolute minimum temperature (°C) | 19.7 | 19.6 | 21.9 | 21.9 | 22.9 | 22.8 | 22.3 | 23.2 | 22.7 | 21.8 | 22.0 | 22.1 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight maximum duration (h) | 11.0 | 11.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 11.0 | 11.0 |
| Daylight mean duration (h) | 11.8 | 11.9 | 12.1 | 12.3 | 12.4 | 12.5 | 12.5 | 12.3 | 12.2 | 12.0 | 11.8 | 11.7 |
| Daylight minimum duration (h) | 11.0 | 11.0 | 11.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 11.0 | 11.0 | 11.0 |
| Sunshine mean duration (h) | 9.4 | 9.8 | 10.3 | 10.2 | 8.5 | 9.0 | 9.7 | 10.8 | 6.7 | 7.1 | 7.4 | 7.6 |
| Precipitation (mm) | 110 | 85 | 154 | 185 | 230 | 373 | 249 | 139 | 576 | 627 | 479 | 416 |
| Sunny days | 11 | 7 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 |
| Rainy days | 20 | 21 | 31 | 29 | 31 | 30 | 31 | 31 | 30 | 30 | 30 | 30 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The largest precipitation sum in Heiyanthuduwa West is at