Thinking of visiting Koh Tao in September? Expect high temperatures reaching 30°C (86°F) during the day, dropping to 27°C (81°F) at night. Heavy showers are common during the rainy season.
September in Koh Tao has its charm, but if you're looking for destinations with pleasant temperatures and sunny skies, our weather planner can help you explore other options in the world.
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Pick a month to see the average temperature, rainfall and sunshine in Koh Tao - and find the best time to visit.
48-year average (1976-2025)
Based on our historical records, temperatures in Koh Tao typically stay consistent throughout September, with daily highs averaging around 30°C (86°F). Nights are warm, with lows around 26°C (79°F).
48-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Browse day-by-day weather records for Koh Tao spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Based on 28 years of weather observations in Koh Tao between 1997 and 2025, these are the recorded extremes.
Find out more about the weather in Thailand and which places have the best travel conditions in this month. See all of Thailand in September →
Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
Warm weather calls for comfortable, breathable clothing in September. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). Also bring a poncho, it will rain a lot! Waterproof everything you can. It won't hurt to bring your sunglasses along, as you'll see some sunny periods.
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Temperature Rainfall Sunshine Humidity
See the full Koh Tao climate overview or explore weather in Thailand.
Where to go in September - average daytime high across popular destinations.
Bangkok
34°C (93°F) Chiang Mai33°C (91°F) Jomtien Beach32°C (90°F) Hua Hin32°C (90°F) Ao Nang Beach30°C (86°F) Koh Samui30°C (86°F) Ko Lanta30°C (86°F) Patong Beach29°C (84°F) Need travel inspiration? Check out our bucket list articles and be inspired.
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