The month in detail
What to expect in September
In September, Koh Tao sees 28°C during the day with 5.4h of sunshine per day. Expect rain on 40% of days — a light raincoat in the bag is recommended.
September ranks 11 out of 12 months in Koh Tao. Compared to August: 8 pts more rainy days, −0.8h of sun per day.
This month's conditions
What it's like in September
UV index
8 · high
sunscreen and hat advised
Feels like
very humid
23°
Sea
30°C
warm, ideal
Daylight
12.1h of daylight
Air quality
good
AQI 20
Compare
Is September the right month?
The best month in Koh Tao is January (8.8/10), 3.6 pts higher than September.
Book
Plan your trip
Hotels at their lowest outside peak season, highest on comfortable months. Shoulder seasons offer a good price/climate compromise.
Stay
Hotels & rentals · Koh Tao
Expedia →
Activities
Tours, tickets, experiences
See ↓
Flights
Multi-airline comparator
Kiwi →
🎟️ Activities & tours · Koh Tao
GetYourGuide selection · free cancellation
Practical info
What you need to know before you go
Three angles: the country (language, currency, safety, budget), the year-round climate, and the specifics of a tropical stay.
Country · Thailand
🗣️LanguageThai
💶CurrencyThai Baht (฿)
🚗DrivingLeft-hand
🛡️Safety ⓘSafe · 2/5
💰Cost of living ⓘCheap · 2/5
🌡️ Climate
🌍Climate typeTropical
📈Climate trend ⓘStable
🔥Hottest monthApril · 29°C
❄️Coolest monthJanuary · 27°C
🌧️Rainiest month ⓘOctober · 50%
🏝️ Tropical stay
🌞Dry season ⓘMay → Sep
🌧️Wet season ⓘDec → Mar
🌀Cyclones ⓘSeason Nov-Apr
Explore
Other destinations in September
If September doesn't convince you for this destination, compare with others.
Location
Where is Koh Tao ?
Global position + regional geographic context.
🌍 World
🔍 Geographic context
ThailandTropical climate with a 8.8 → 5.0 gap between best and worst month. 10 years of ERA5 data to choose by project.
10.10°N · 99.84°E
Questions
Frequently asked questions
What is the best time to visit Koh Tao?
January is the best month with 27.0°C highs, 25.0°C lows, 7.8h of sunshine and 15.0% rainy days. The months of January & February offer comparable conditions.
How many hours of sunshine does Koh Tao get in January?
Koh Tao averages 7.8 sunshine hours per day in January. It is the sunniest month with a climate score of 8.3/10.
What is the rainiest month in Koh Tao?
October is the most unfavourable month with October has the lowest climate score of the year and the lowest climate score of the year.
What are the temperatures at night in Koh Tao in January?
In January, overnight lows reach 25.0°C, while afternoon highs average 27.0°C.
Is Koh Tao good in winter?
In winter (December-February), Koh Tao scores 7.4/10 on average — Decent period conditions for cultural visits.. The best month overall remains January with a score of 8.3/10.
When should you avoid Koh Tao?
October is the most difficult month to visit Koh Tao, with October has the lowest climate score of the year. Climate conditions are at their lowest of the year during this period.
Can you swim in Koh Tao in September?
In September, the sea averages 30°C in Koh Tao: warm, ideal. Ideal conditions for swimming and snorkeling.
Do you need sun protection in Koh Tao in September?
The average UV index reaches 8 in September in Koh Tao (high), with about 12.1h of daylight. Sunscreen and hat advised.