Average annual temperature is 26.7 °C
Absolute maximum temperature: 39.7 °C
Absolute minimum temperature: 19.4 °C
Number of sunny days: 45 days
Number of rainy days: 320 days
Look at detailed online map of Heraliwatta
* Weather data for Heraliwatta 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) | 29.0 | 30.6 | 32.9 | 35.1 | 35.7 | 37.4 | 39.2 | 39.7 | 35.5 | 32.0 | 30.6 | 30.6 |
| Average daytime temperature (°C) | 27.9 | 28.3 | 29.9 | 31.9 | 32.5 | 35.5 | 35.7 | 37.7 | 33.1 | 30.3 | 29.3 | 28.6 |
| Average temperature (°C) | 24.1 | 24.6 | 25.6 | 26.8 | 27.5 | 29.1 | 29.2 | 30.2 | 27.6 | 25.7 | 25.2 | 25.1 |
| Average night temperature (°C) | 21.3 | 21.7 | 22.4 | 23.2 | 23.9 | 24.7 | 24.5 | 24.9 | 24.3 | 22.9 | 22.8 | 22.9 |
| Absolute minimum temperature (°C) | 19.4 | 19.9 | 21.6 | 21.7 | 22.3 | 23.7 | 23.2 | 23.9 | 22.9 | 22.0 | 22.1 | 22.0 |
| 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) | 9.2 | 9.1 | 9.5 | 9.9 | 9.4 | 10.5 | 9.8 | 10.9 | 9.6 | 8.4 | 7.4 | 7.3 |
| Precipitation (mm) | 107 | 149 | 136 | 118 | 198 | 64 | 63 | 50 | 129 | 362 | 485 | 377 |
| Sunny days | 9 | 8 | 4 | 1 | 8 | 4 | 4 | 6 | 1 | 0 | 0 | 0 |
| Rainy days | 22 | 20 | 27 | 29 | 23 | 26 | 27 | 25 | 29 | 31 | 30 | 31 |
| Snow days | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
The largest precipitation sum in Heraliwatta is at