Koh Tao Weather in September
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.
Rainfall in Koh Tao in September
Koh Tao is in the rainy season in September, with rain on around 18 days and an average of 202 mm (8 in). The rainy season here brings regular, substantial showers. It's worth being prepared for rain on most days you're out.
Temperature in Koh Tao in September
In September, Koh Tao gets high temperatures, with highs of 30°C (86°F). Nights cool to around 27°C (81°F). Conditions stay fairly consistent through the month, making it easier to plan what to wear. With overnight lows of 27°C (81°F), nights stay very warm. Air conditioning makes a real difference if you're sensitive to heat. A cold shower before bed can also help you get to sleep more comfortably.
Sunshine in Koh Tao in September
The city usually sees around 146 hours of sunlight, indicating a moderately sunny period (despite it being part of 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.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Thailand, check out our Koh Tao's climate page.
Koh Tao Temperature in September
Min Temperature
27°C (81°F)
Max Temperature
30°C (86°F)
Chance of Rain
61%
Precipitation
202 mm (8 in)
Rainy days
18 days
Humidity
80% *
Sunshine
146 hours *
Percentage Sunshine
*
Daily Historical Temperatures
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).
Average temperatures in September
Daily Historical Precipitation
48-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Koh Tao in September
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.
Koh Tao historical weather extremes in September
Based on 28 years of weather observations in Koh Tao between 1997 and 2025, these are the recorded extremes.
- On September 5, 2025, temperatures climbed to 35°C (95°F), marking the warmest September day on record.
- Koh Tao experienced its chilliest September day on September 16, 2014, reaching only 27°C (81°F).
- Koh Tao registered its coldest September night on September 25, 2012, with temperatures dropping to 20°C (68°F).
- The wettest September day on record brought 117 mm (4.6 in) of precipitation to Koh Tao (September 6, 2005).
Best Places in Thailand in September
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
pleasant
tolerable
unpleasant
poor
What to Wear in Koh Tao in September
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.What To Do in Koh Tao in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Thailand, check out our Koh Tao's climate page.
Temperature Rainfall Sunshine Humidity
See the full Koh Tao climate overview or explore weather in Thailand.
