Ko Chang (Koh Chang) weather by month
The best time to visit Ko Chang (Koh Chang) is December to February — 92/100 in December, 31°C and 5 rainy days. The best season is the dry season, November to April (85/100 on average).
The worst month is September at 49/100 — sweltering, soaked, clean air. See September →
Updated September 2026 · climate normals from ERA5 reanalysis
Planning the wider trip? Best time to visit Thailand →
Best season: November to April (85/100 on average) · worst September (49/100)
- Days
- 31°C
- Nights
- 25°C
- Wet days
- 5
- Sun
- 9.7 h
- Humidity
- 70%
- Daylight
- 11 h

Ko Chang, month by month
Comfort score out of 100 for the kind of trip Ko Chang is best for, the average high, rainy days and hours of sun a day from the climate normals, and how busy it tends to be.
What's on in Ko Chang through the year
Festivals, natural spectacles, holidays and the seasons to watch out for — curated and sourced. The month pages carry the detail.
Crowds in Ko Chang in December
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.
Peak crowdstravelers describe it as peak season, High season on the island, Christmas and New Year peak
Sourced from traveler notes: “…tioning and just leave the window open instead. December is peak season across Thailand, so posters note it's also one of the busie…” — Tripadvisor community
Peak crowdsBusyShoulder seasonQuiet
Traveller notes on Ko Chang
What people who have been say about the place — the year-round notes first, then month by month.
Ko Chang's forum is honest that June is historically one of the wettest months on the island, and which kind of week you get - mostly sunny with a passing shower, or grey and wet for days - genuinely comes down to luck. Posters were consistent that it's rare for rain to last an entire day; more often it's a short afternoon shower or a late-night thunderstorm. The trade-off for accepting rougher seas and real rain risk is a much quieter island and waterfalls running at their most spectacular - some visitors specifically choose this season for the jungle and falls over the beach.
Forum posters describe December as close to ideal here - sunny, not too hot, minimal rain expected, with the sea reported flat, clear and calm under bright blue skies from November onward. Daytime highs are commonly described in the low-30sC, with overnight temperatures posters call cool by tropical-island standards - typically settling in the low-to-mid-20sC, though a windier night can feel noticeably chilly to some visitors, prompting a few to skip the air conditioning and just leave the window open instead. December is peak season across Thailand, so posters note it's also one of the busier, pricier months, with the island reported quieter only in the first couple weeks before the holiday rush sets in.
Add your own note from Ko Chang's card on the map.