Koh Samui Climate

Generally

Koh Samui's climate is tropical. It can have periods of high temperature and high humidity. The average temperature is about 30 degrees Celsius or 86 degrees Fahrenheit. Even though the world weather is quite unpredictable nowadays it is more or less sunny all year round on Koh Samui and you could say that it generally has three seasons as follows:

Dry Season

December to February is generally called the dry season. There is normally not much rain but there can be some refreshing winds on the island at this time. It is great for sailing and other water sport activities. The sun is normally shining a lot at this time of year and the water conditions are usually calm and great for swimming.

Hot season

March to September is the hottest season on Koh Samui. The weather is very dry and rather hot in this time of year. In May and June however, you can experience a little increase in the rain. This is a great period to visit Samui, if you can stand 30-35 degrees Celsius during the daytime. Songkran, the Thai New Year, is celebrated between the 12th and 14th of April. This is the largest water splashing festival in the whole of South East Asia.

Rainy season

October to November is generally considered to be the rainy or monsoon season. It is still hot during the daytime and there can be many sunny days. However, the evenings generally get getting cooler and you may need some warmer clothes. Sometimes the refreshing monsoon showers only last a moments and then it clears up again. However the monsoon is different every year and it can vary from a whole week of non stop rain to daily afternoon showers; no years are the same.

Average Monthly Climatic Conditions