Climate averages 1991–2020
Colombo weather
in August.
A hot, wet month: the coolest and the 6th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a hot month in Colombo: daytime highs average 28.4°C and nights cool to about 24.6°C. By daytime temperature it is the coolest month of the year.
Expect about 168 mm of rain on roughly 24 days, which makes August a wet month (the 6th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 21 min on an average August day.
The nearest other city in this atlas is Dehiwala-Mount Lavinia (11 km away). In August its highs average 28.1°C, about as warm as Colombo, with 183 mm of rain.
Among the 12 cities listed in Sri Lanka, Colombo ranks joint 7th of 12 for the warmest August highs and 10th of 12 for the driest August (rainfall, lowest first). The mean August high of those 12 cities is 30.0°C; Colombo is 1.6°C cooler than that mean.
From August to September, average highs rise by 0.1°C to 28.5°C, and monthly rainfall rises from 168 mm to 223 mm.
The annual picture
August in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Colombo climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 30.4°C22.9°C | 22.9°C | 53 | 7.8 | 11.812 h |
| February | 31.5°C23.4°C | 23.4°C | 55 | 7.8 | 11.912 h |
| March | 31.6°C24.4°C | 24.4°C | 75 | 14.9 | 12.112 h |
| April | 30.8°C25.0°C | 25.0°C | 167 | 24.8 | 12.312 h |
| May | 29.5°C25.4°C | 25.4°C | 279 | 28.9 | 12.412 h |
| June | 28.8°C25.1°C | 25.1°C | 242 | 26.7 | 12.513 h |
| July | 28.5°C24.8°C | 24.8°C | 183 | 24.4 | 12.512 h |
| August, selected | 28.4°C24.6°C | 24.6°C | 168 | 23.6 | 12.312 h |
| September | 28.5°C24.5°C | 24.5°C | 223 | 24.5 | 12.212 h |
| October | 28.8°C24.1°C | 24.1°C | 327 | 26.0 | 12.012 h |
| November | 29.0°C23.6°C | 23.6°C | 307 | 23.7 | 11.812 h |
| December | 29.2°C23.2°C | 23.2°C | 164 | 15.6 | 11.712 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
August in nearby cities
- Dehiwala-Mount Lavinia in AugustSri Lanka · 11 kmHigh 28.1°C · Low 24.7°C · 183 mm rain
- Negombo in AugustSri Lanka · 30 kmHigh 28.4°C · Low 25.0°C · 165 mm rain
- Kandy in AugustSri Lanka · 95 kmHigh 26.8°C · Low 21.1°C · 90 mm rain
- Galle in AugustSri Lanka · 107 kmHigh 27.7°C · Low 24.8°C · 207 mm rain
- Matara in AugustSri Lanka · 133 kmHigh 28.2°C · Low 24.7°C · 159 mm rain
- Ambalantota in AugustSri Lanka · 158 kmHigh 31.2°C · Low 25.3°C · 52 mm rain
- Batticaloa in AugustSri Lanka · 221 kmHigh 34.2°C · Low 26.1°C · 31 mm rain
- Kalmunai in AugustSri Lanka · 225 kmHigh 32.8°C · Low 26.1°C · 42 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Colombo) is explained once on the Colombo year overview and on the Sources, method and limits page.