SeasonMapKo Tao (Koh Tao) weather in September
Thailand
September in Ko Tao: hot, soaked, with clean air — fine if you can take 22 rainy days.
#10 of 12 months in Ko Tao · #934 of 1383 destinations to visit in September · comfort 70/100 (tier B)
Updated September 2026 · climate normals from ERA5 reanalysis
Traveller notes on Ko Tao in September
Other months in Ko Tao
Ko Tao's forum calls March a good window as the seas calm after the rainy season — flat water and great visibility for diving, with only occasional cloudy days and the odd rain shower rather than a washout. Regulars flag the humidity as climbing as the hot season sets in, though it's not yet the peak heat of April-June.
Add your own note from Ko Tao's card on the map.
Ko Tao climate normals — September
| Daytime high | 27°C / 81°F | 🥵 hot |
|---|---|---|
| Nighttime low | 26°C / 78°F | |
| Feels like (high) | 31°C / 88°F | |
| Sea temperature | 30°C / 85°F | ♨️ bath-warm |
| Rainfall | 182 mm / 7.1 in | ⛈ soaked |
| Rainy days | 22 days | |
| Humidity | 81% | 💦 very humid |
| Dew point | 23°C / 73°F | |
| Sunshine | 8.3 h/day | |
| Daylight | 12.2 h | |
| Wind | 25 km/h / 16 mph | |
| Air quality (US AQI) | 29 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Ko Tao in September
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
BusyClear water, dive season, school holidays in 3 of the markets that fill it(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Ko Tao's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Toughest weatherKo Tao's weather peaks February–April, best around March.
Best weatherFair weatherToughest weather
What's on in Ko Tao in September
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Season
Clear water, dive season
1 Feb – 30 Sep · usuallyDry seasonCrowdedThe settled half of the Gulf year, when the boats to Chumphon Pinnacle and Sail Rock go out every day and the training courses run back to back. Visibility is at its best on the shoulder months.
Nearby, and something's on
Within 300 km of Ko Tao — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Ko Tao?
Ko Tao in September — FAQ
- Is September a good time to visit Ko Tao?
- September in Ko Tao: hot, soaked, with clean air — fine if you can take 22 rainy days. It ranks #10 of 12 months for Ko Tao on SeasonMap's comfort score (70/100).
- What is the weather like in Ko Tao in September?
- In September, Ko Tao averages a daily high of 27.2°C and a low of 25.6°C, with about 181.5 mm of rain over roughly 22.1 rainy days.
- What is the air quality in Ko Tao in September?
- Ko Tao has a mean US Air Quality Index of about 29 in September.
Other months in Ko Tao
Compare Ko Tao in September
Warmer or cooler than Ko Tao in September
Similar destinations in Southeast Asia — September
Within 300 km: Ko Pha Ngan's Full Moon Party on 1 Jan – 31 Dec, and Khao Sok's Southwest monsoon around 1 May – 30 Sep.