The weather in Koh Samui in January is very hot. The average temperatures are between 26°C and 27°C, drinking water regularly is advisable.
You can expect rain for roughly half of the month of January in Koh Samui. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Koh Samui in January 2025.
If you’re planning to visit Koh Samui in the near future, we highly recommend that you review the 14 day weather forecast for Koh Samui before you arrive.
Temperatures
27° / 26°
Rainy Days
8
Snowy Days
0
Dry Days
23
Rainfall
326
mm
Sun Hours
10.9
Hrs