Practical guide
Monsoon in the west, decent weather on the Gulf, and Maya Bay closed.
August is deep in the rainy season for most of Thailand, but the Gulf coast is the exception. Koh Samui, Koh Phangan, Koh Tao and Hua Hin stay decent, with far less rain than Phuket and Krabi, where the monsoon brings rough seas and canceled boats. Chiang Mai has its wettest month, Koh Chang is very wet, and Maya Bay on Phi Phi is closed from 1 August to 30 September. For a summer-holiday trip, book the Gulf islands and Bangkok and you'll do fine.
Averages for eight weather stations, one for each part of the country. Tap a region in the table to jump to it, or switch to °F and inches.
| Region | High | Low | Rain | Rain days | Sea |
|---|---|---|---|---|---|
| Bangkok | 33°C | 26°C | 227 mm | 16 | – |
| Chiang Mai | 32°C | 24°C | 223 mm | 17 | – |
| Phuket | 32°C | 26°C | 309 mm | 17 | 29°C |
| Koh Samui | 32°C | 25°C | 102 mm | 10 | 29°C |
| Pattaya | 31°C | 26°C | 91 mm | 9 | 29°C |
| Hua Hin | 33°C | 26°C | 67 mm | 10 | – |
| Koh Chang | 31°C | 24°C | 970 mm | 25 | 30°C |
| Isan | 32°C | 24°C | 222 mm | 14 | – |
Central plains and the capital
Highs of 33°C and lows of 26°C, 227 mm of rain on about 16 days, 4.2 hours of sun a day.
One of the wetter months, with a downpour on most days and some flooded streets after the heaviest storms. Plan around the BTS and MRT.
The north: Chiang Mai, Chiang Rai, Pai
Highs of 32°C and lows of 24°C, 223 mm of rain on about 17 days, 3.6 hours of sun a day.
The wettest month of the year in the north. Lush and green, with full waterfalls and muddy trails.
Andaman coast: Phuket, Krabi, Koh Lanta, Khao Lak
Highs of 32°C and lows of 26°C, 309 mm of rain on about 17 days, sea at 29°C.
Deep monsoon on the Andaman coast, with heavy rain, big swell and ferry cancellations. Maya Bay on Phi Phi is closed for the whole month.
Gulf islands: Koh Samui, Koh Phangan, Koh Tao
Highs of 32°C and lows of 25°C, 102 mm of rain on about 10 days, sea at 29°C.
Decent weather on the Gulf islands, with far fewer rain days than the west coast. Koh Samui, Koh Phangan and Koh Tao are the beach choice.
Upper Gulf: Pattaya, Koh Samet, Rayong
Highs of 31°C and lows of 26°C, 91 mm of rain on about 9 days, sea at 29°C.
Showers, but drier than most of the coast, with the sea sheltered in the upper Gulf.
Western Gulf: Hua Hin, Cha-am, Pranburi
Highs of 33°C and lows of 26°C, 67 mm of rain on about 10 days, 4.3 hours of sun a day.
One of the driest beach towns in August, with light showers and plenty of sun.
Eastern seaboard: Koh Chang, Koh Kood, Koh Mak
Highs of 31°C and lows of 24°C, 970 mm of rain on about 25 days, sea at 30°C.
Very wet, with rain on most days, and some smaller resorts are closed for the season.
Northeast: Khon Kaen, Udon Thani, Korat, Buriram, Ubon
Highs of 32°C and lows of 24°C, 222 mm of rain on about 14 days, 4.1 hours of sun a day.
Rainy season and green rice fields across the northeast.
Source WMO Climatological Standard Normals 1991–2020 (Thai Meteorological Department stations). Averages for 1991–2020, and rain days count days with at least 1 mm. Sea temperatures: Climates to Travel monthly sea-surface averages. Koh Chang uses the Trat station on the facing mainland and Isan uses Khon Kaen.
Arriving in Koh Samui
Pick a region from this page, then the area. The dates start mid-August, so change them to your own and the search follows. Filter for free cancellation if you want to hold a room while you settle the route.
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August has one national holiday.
The birthday of the late Queen Sirikit is a public holiday and Thailand's Mother's Day.
Haad Rin, Koh Phangan, in the Gulf islands' good season.
A light jacket or a compact umbrella. Expect a storm most days outside the Gulf.
For flooded streets and clothes that need to dry overnight.
For ferries and any boat trip.
Ferries and boat trips get canceled in rough weather.
Common questions about thailand in august.
Other months, and the whole year at a glance
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Written by
Mac Kiley
I lived in Bangkok for four years and traveled the country from there. The guides are my own opinions, written the way I'd explain them to a friend planning a trip.
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