September in Koh Tao brings a mix of warm temperatures and frequent rain. The highs can reach up to 31°C, making the days quite hot. On the other hand, the lows dip to a more comfortable 26°C, offering a bit of relief from the heat. The wind speed averages around 10 km/h, adding a gentle breeze to the warm days.
Rainfall is quite significant in September, with up to 130 mm expected throughout the month. This means there are plenty of wet days, so it’s a good idea to pack an umbrella or raincoat. Despite the rain, the sun does make an appearance, although not as much as in the drier months. Overall, the weather in Koh Tao in September is a blend of tropical heat and refreshing rain.
