Climate and Weather of Koh Samui, Thailand

In Thailand you have several regions, one of which is called Koh Samui. The most popular city in this region is Chaweng Beach, whose climate data we'll examine to provide you with an overview of what weather to expect in Koh Samui. For detailed climate information about other cities in the area, please refer to the section beneath the map further down the page.

One thing to take into account is that on average, the temperatures are always high. The coldest month is January with an average maximum temperature of 28°C. However, the specific temperature can vary depending on the exact location within the region.

Additional climate insights:

• Most rainfall (rainy season) is seen in September, October, November and December.
• October is the wettest month in Koh Samui. This month should be avoided if you are not a big fan of rain.
• February is the driest month.
• The warmest month in Koh Samui is May with an average maximum temperature of 30°C.
• The coldest month is January with an average maximum daytime temperature of 28°C.
• March is the sunniest month in Koh Samui.

The second largest island in Thailand is a beautiful destination all year round. From January to December the temperatures on Koh Samui are around 30°C.

It has two rainy seasons, one from May to August, just like in the rest of Thailand. The second usually starts in October, and is part of the monsoon season. These rains are very heavy and last a long time, and stay until December. In the first rainy season it rains much less in Koh Samui compared to the rest of Thailand.

The best months to visit are the months of January, February and March. It can be a bit busy during this period so it is recommended to book a place to stay in advance.

Interested in the detailed Weather and Climate of Koh Samui, Thailand?

Please select a city below the map you wish to travel to, or the one closest to your destination. Each selected city will show you the following graphs:
1. Average minimum and maximum temperature over the year
2. Average monthly precipitation over the year (rainfall, snow)
3. Average monthly hours of sunshine over the year
On certain pages we also offer other historical climate data like humidity wind speed and water temperature.