Ko Chang (Koh Chang) weather in May
May in Ko Chang: sweltering, soaked, with clean air — a gamble, with 29 rainy days.
Updated September 2026 · climate normals from ERA5 reanalysis
#7 of 12 months in Ko Chang · #1166 of 1413 destinations to visit in May · comfort 61/100 (tier C)
- Days
- 32°C
- Nights
- 28°C
- Wet days
- 29
- Sun
- 9 h
- Humidity
- 84%
- Daylight
- 13 h

Traveller notes on Ko Chang in May
Other months in Ko Chang
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.
Ko Chang climate normals — May
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Ko Chang in May
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.
BusyLong summer break in Thailand, school holidays in 2 of the markets that fill it(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Ko Chang's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherKo Chang's weather peaks December–February.
Best weatherFair weatherToughest weather
What's on in Ko Chang in May
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Season
Low-season shutdown
15 May – 15 Oct · usuallyOff-season shutdownClosuresSwell on the west coast, half the resorts and most of the dive shops closed, and the beach bars boarded up. What stays open is cheap and quiet, and the waterfalls are running.
- Season
Wet season
MonsoonRisk29 rainy days and about 335 mm in the month — the real kind of rainy season, not afternoon showers.
from the climate normals
Nearby, and something's on
Within 300 km of Ko Chang — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Ko Chang?
Ko Chang in May — FAQ
- Is May a good time to visit Ko Chang?
- May in Ko Chang: sweltering, soaked, with clean air — a gamble, with 29 rainy days. It ranks #7 of 12 months for Ko Chang on SeasonMap's comfort score (61/100).
- What is the weather like in Ko Chang in May?
- In May, Ko Chang averages a daily high of 31.7°C and a low of 28°C, with about 335.1 mm of rain over roughly 28.8 rainy days.
- What is the air quality in Ko Chang in May?
- Ko Chang has a mean US Air Quality Index of about 42 in May.
Within 300 km: Bangkok's Bangkok Pride around 28 May – 10 Jun, and Siem Reap's Southwest monsoon around 15 May – 31 Oct.