Ko Samui weather in August
August in Ko Samui: sweltering, a little rain, with clean air — an excellent time to visit.
#4 of 12 months in Ko Samui · #234 of 604 destinations to visit in August · comfort 83/100 (tier A)
Updated June 2026 · climate normals from ERA5 reanalysis
Ko Samui climate normals — August
| Daytime high | 30°C / 86°F | 🔥 sweltering |
|---|---|---|
| Nighttime low | 27°C / 81°F | |
| Feels like (high) | 35°C / 95°F | |
| Rainfall | 78 mm / 3.1 in | 🌦 some rain |
| Rainy days | 17 days | |
| Humidity | 76% | 💦 very humid |
| Dew point | 24°C / 75°F | |
| Sunshine | 9.6 h/day | |
| Daylight | 12.4 h | |
| Wind | 23 km/h / 14 mph | |
| Air quality (US AQI) | 27 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Where is Ko Samui?
Loading map…
Ko Samui in August — FAQ
- Is August a good time to visit Ko Samui?
- August in Ko Samui: sweltering, a little rain, with clean air — an excellent time to visit. It ranks #4 of 12 months for Ko Samui on SeasonMap's comfort score (83/100).
- What is the weather like in Ko Samui in August?
- In August, Ko Samui averages a daily high of 29.9°C and a low of 27.1°C, with about 77.8 mm of rain over roughly 16.8 rainy days.
- What is the air quality in Ko Samui in August?
- Ko Samui has a mean US Air Quality Index of about 27 in August.