Due to its proximity to the equator, the climate on Koh Phangan is tropical. The weather on Koh Phangan is best described by the average temperature of 25 ℃ – 34 ℃, with lots of sunshine, high humidity and – as the word tropical rainforest implies – the occasional showers.

The average annual rainfall is about 1,800 millimeter, February has the lowest average of about 34 millimeter whereas November has the highest average of about 450 millimeter.

The weather is pretty constant during the year but roughly there are three main seasons on Koh Phangan: the dry season (mid December – April) when it is mostly dry and relatively cool, the hot season (May – September), when it can be very hot with occasional storm showers and the wet season (October – mid December), when there can be a strong and windy monsoon and a lot of rain. However, like in every country the weather can be unpredictable and local: on one part of koh Phangan you might lie on the beach while on the other side you may have to shelter for a scattered thundershower.

There are roughly two tidal seasons on Koh Phangan: April to November (low) and November to April (high). In low tidal season swimming on the West coast is not always possible during certain hours of the day due to sand banks and shallow water, where as it is possible on the Northeast side of the island.

Overall we would say the best time to visit Koh Phangan is from January to August, when the weather conditions are usually at their best. If you like a tan, be aware that the sun can be extremely strong. Even on a cloudy day you can get sunburned easily.