Best Time to Visit Ko Samui
Thailand · 30-year monthly climate averages
☀️ When to go
Based on 30 years of climate data, the most comfortable months to visit Ko Samui are January, February and April, when daytime temperatures are agreeable and rainfall is relatively low.
Climate profile
Ko Samui sees its warmest weather in May, when daytime highs average around 33°C, and its coolest in January (around 29°C).
Annual precipitation totals roughly 1994mm — November is typically the wettest month (~445mm) and February the driest (~64mm).
A distinctly wetter period runs from September to January — worth planning around if you prefer dry days.
Year at a glance
🟧 avg daytime high · 🟦 dashed: avg nighttime low · bars: monthly rainfall
🔥 Recent heat vs normal
Daily forecast highs vs the 30-year normal — last 37 days
Each bar is one day: orange above normal, blue below.
Month by month
| Month | High / Low | Rainfall | Travel rating |
|---|---|---|---|
| January | 29° / 24°C | 127mm | 👍 Good |
| February | 29° / 25°C | 64mm | 👍 Good |
| March | 30° / 25°C | 116mm | 🤔 Fair |
| April | 32° / 26°C | 83mm | 🤔 Fair |
| May | 33° / 26°C | 132mm | 🤔 Fair |
| June | 33° / 25°C | 134mm | 🤔 Fair |
| July | 32° / 25°C | 117mm | 🤔 Fair |
| August | 32° / 25°C | 102mm | 🤔 Fair |
| September | 32° / 25°C | 118mm | 🤔 Fair |
| October | 31° / 24°C | 295mm | ⚠️ Challenging |
| November | 30° / 24°C | 445mm | 🤔 Fair |
| December | 29° / 24°C | 263mm | 🤔 Fair |
FAQ
- What is the best time to visit Ko Samui?
- Based on 30 years of climate data, the most comfortable months to visit Ko Samui are January, February and April, when daytime temperatures are agreeable and rainfall is relatively low.
- What is the hottest month in Ko Samui?
- May is typically the hottest month in Ko Samui, with average daytime highs around 33°C.
- What is the rainiest month in Ko Samui?
- November is usually the wettest month, with around 445mm of precipitation.