Koh Samui - Climate

Seasons in the sun

The Koh Samui climate is divided into three seasons which goes for more parts of Thailand, though not for all. The three seasons of Koh Samui are: 

  1. The dry season: December-February 
  2. The hot season: March-August
  3. The rainy season: September-November

The Monsoon

The rainy season, also called the Monsoon, takes place between the months of September and November on Koh Samui. The preceding moths are hotter that the average while the months following after the Monsoon are a bit cooler. The dry season, which are the cooler ones, are the peak months for tourism as they are known to be the most pleasant weather-wise. 


The Koh Samui climate is usually described as a tropical savannah climate containing only a single dry month. The air on Koh Samui is hot and humid almost every day of the year, with minor variations. In comparison to other popular Thailand destinations Koh Samui is, however, considered slightly drier. The coolest months are January-February but the variations are small. 

The best time to visit Koh Samui

Most people visiting Koh Samui do so to enjoy the sunshine, the warm sea, good food and spectacular views. To really be able to enjoy all of this it’s important for the weather to be dry and sunny. 

It’s never cold on Koh Samui, but some months are rainier than other, December, for example, has its fair share of showers even though they usually pass quickly. Quite often the showers are a welcome interruption of the ever beaming sunrays. December-March are the most popular months for tourists on Koh Samui as well as for the rest of Thailand. 

During the European summer months Koh Samui is very hot and humid.