Yearly weather and climate in Ko Samui, Thailand
The yearly weather in Ko Samui runs from around 25°C in January to 33°C in April. April is the driest month at 6 rainy days; October the wettest at 29. Here is the annual climate data, so you know what you are packing for.
Best time to visit
Weather is fairly consistent year-round. Pack for stable conditions.
Sunshine
Expect up to 11.7 hours of clear skies in Apr, but only 7.9 hours in Jul. Pack sunglasses and SPF accordingly.
Rainfall
It rains the most in Nov (279mm over 26 days). A reliable rain jacket is a must-have if visiting then.
Day-to-night swings
Temperatures typically drop by 4°C from day to night. Make sure to pack layers for the evenings.
Average temperatures and rainfall
Daily highs and lows in Ko Samui, averaged over 10 years of recorded weather, with the number of days it typically rains.
- 2984°2576°15Jan
- 3086°2577°13Feb
- 3188°2679°9Mar
- 3392°2781°6Apr
- 3290°2781°22May
- 3188°2780°18Jun
- 3086°2679°23Jul
- 3087°2678°23Aug
- 2985°2678°25Sep
- 2985°2577°29Oct
- 2984°2576°26Nov
- 2883°2577°25Dec
Bars span the average daily low to high. Numbers under the drop are rainy days per month (1mm or more) — hover a month for its total rainfall. Apr is typically driest at 6 days (23mm); Oct the wettest at 29 days (235mm).
| Month | Average high | Average low | Rainy days | Total rainfall |
|---|---|---|---|---|
| Jan | 29°C | 25°C | 15 | 56mm |
| Feb | 30°C | 25°C | 13 | 44mm |
| Mar | 31°C | 26°C | 9 | 24mm |
| Apr | 33°C | 27°C | 6 | 23mm |
| May | 32°C | 27°C | 22 | 110mm |
| Jun | 31°C | 27°C | 18 | 113mm |
| Jul | 30°C | 26°C | 23 | 188mm |
| Aug | 30°C | 26°C | 23 | 170mm |
| Sep | 29°C | 26°C | 25 | 211mm |
| Oct | 29°C | 25°C | 29 | 235mm |
| Nov | 29°C | 25°C | 26 | 279mm |
| Dec | 28°C | 25°C | 25 | 187mm |
Weather data by Open-Meteo.com
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