Ko Tao (Koh Tao) weather in August
August in Ko Tao: hot, rainy, with clean air — fine if you can take 19 rainy days.
Updated September 2026 · climate normals from ERA5 reanalysis
#6 of 12 months in Ko Tao · #721 of 1413 destinations to visit in August · comfort 79/100 (tier B)
- Days
- 28°C
- Nights
- 26°C
- Wet days
- 19
- Sun
- 9.3 h
- Humidity
- 80%
- Daylight
- 12 h

Traveller notes on Ko Tao in August
Notes from nearby Ko Pha Ngan (45 km away)
Ko Tao doesn't have its own notes for August yet — these are about Ko Pha Ngan, close enough to share the season.
Regulars are specific this island stays largely sheltered from the prevailing weather by the Thai mainland, the same effect that makes nearby Koh Samui a reliable choice this time of year, occasional heavy showers the exception rather than the rule. Our row backs that hot, genuinely wet read, 30.8C reading as a scorching 35C, over 26.2C nights feeling 29C, with a substantial 111.6mm of rain across 19.6 days and humidity at 79 percent. Regulars are honest experiences do vary though, some visitors reporting rain most evenings, three or four times a week, occasionally flooding roads and washing sand up onto walkways. Seas generally stay calm enough for good boat trips and water activities regardless. The sea sits at a bath-warm 30C. The record: 9.5 hours of sun, a 25.8 kph wind and AQI 27.
Other months in Ko Tao
Regulars are specific this island's own monsoon doesn't actually arrive until October or November, this month instead falling within a Gulf-coast stretch that regulars call usually pretty good, cooled slightly from the hottest months and genuinely quieter than peak season. Our row backs that hot, genuinely wet read, 28.2C reading as a hot 32C, over 26.3C nights feeling 29C, with a substantial 111.8mm of rain across 18.8 days and a real 24.2 kph wind. Regulars are honest the weather stays genuinely hard to predict day to day, capable of being fantastic, bringing a few rainstorms, or just turning windy, with most water flat except a sheltered stretch on the east coast worth seeking out. The sea sits at a bath-warm 30.1C. The record: 9.3 hours of sun, humidity 79 percent and AQI 33.
Koh Tao-forum threads on July weather call it hot and mostly sunny, with dramatic electrical storms visible out over the mainland most nights - a genuine spectacle rather than a disruption, since they rarely reach the island itself. Rain does show up, but posters are split on how much: some describe it as roughly half sun and half rain across July and August, others call it noticeably cooler with occasional evening showers that come as a welcome break from the heat. The consistent thread is that any given shower rarely lasts more than an hour, clearing back to sun and good snorkeling visibility quickly. Regulars recommend Koh Tao over Thailand's west-coast islands this time of year, since the Andaman side takes the brunt of the real monsoon. The record: 27.8C days feeling like a sticky 31C, 26C nights, 135mm across 20.5 days, 80 percent humidity, a 29.9C sea and wind averaging over 25 km/h.
Koh Tao-forum threads comparing it to Koh Lanta for early January make the geography plain: the Gulf coast, where Koh Tao sits, runs its monsoon roughly November through March, while the Andaman coast opposite is already in its dry season by November - so 'Thailand in January' means two different climates depending which coast you pick. Regulars note the monsoon has historically been mostly a November event here, but recent years have seen it linger later, cold and rainy conditions and rough, low-visibility diving stretching into mid-February in a bad year. Early January specifically can still carry wind and chop left over from December, improving gradually week by week rather than all at once. The peak diving season proper doesn't arrive until February through May. The record: 26.1C days feeling like 29C, 25.1C nights, 101mm across 8.7 days, a 27.3C sea, 78 percent humidity, wind averaging nearly 23 km/h and 10.3 hours of sun.
April is the hottest month in Thailand and regulars say Koh Tao takes the edge off it - an island with a sea breeze rather than a mainland city - while still being stifling through the middle of the day. February to April is the driest stretch here, and what rain there is tends to be a quick shower in the late afternoon or early evening rather than anything that costs you a day. Some divers name late April and May specifically, on the grounds that the weather is usually settled and the island is quieter, and accept the heat as the price. Our row's 28.2C reads as 34C at 78 percent humidity, with a 30.6C sea. The record: 26.7C nights, 11.6 precipitation days carrying 104.5mm and 10.7 hours of sun.
Add your own note from Ko Tao's card on the map.
Ko Tao climate normals — August
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Ko Tao in August
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 4 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).
Fair weatherKo Tao's weather peaks February–April, best around March.
Best weatherFair weatherToughest weather
What's on in Ko Tao in August
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 August — FAQ
- Is August a good time to visit Ko Tao?
- August in Ko Tao: hot, rainy, with clean air — fine if you can take 19 rainy days. It ranks #6 of 12 months for Ko Tao on SeasonMap's comfort score (79/100).
- What is the weather like in Ko Tao in August?
- In August, Ko Tao averages a daily high of 27.7°C and a low of 25.9°C, with about 121 mm of rain over roughly 19 rainy days.
- What is the air quality in Ko Tao in August?
- Ko Tao has a mean US Air Quality Index of about 29 in August.
Within 300 km: Ko Pha Ngan's Gulf dry season around 15 Jan – 31 Aug, and Ko Samui's Gulf dry season around 15 Jan – 31 Aug.