Koh Samui weather live forecast

Today's maximum temperature in Koh Samui is expected to be 31°C. Select a day from the live weather forecast for Koh Samui, Thailand for more weather parameters.

Tuesday
16th Dec
31

25

6

9
Wednesday
17th Dec
30

26

8

9
Thursday
18th Dec
30

26

6

9
Friday
19th Dec
30

26

7

9
Saturday
20th Dec
31

26

7

9

5-day weather forecast updated at 04:01 on Tuesday 16th December 2025 GMT

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The 5-day weather forecast for Thailand (Koh Samui) is provided by the Swiss meteorological agency, meteoblue. Find out more about our data sources.

Koh Samui weather forecast by day

Below are the detailed weather forecasts for Koh Samui for the next 5 days.

Koh Samui weather for Tuesday 16th December 2025

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 6 hours of bright sunshine. There are 5-10 mm of rainfall expected with 35% chance of some rain and a gentle breeze of 13 kph from the north-east.

31
°C maximum temperature
25
°C minimum temperature
isolated thunderstorms
6
hours of sunshine
9
UV index (Very High)
35
% chance of some rain
<10
mm of rainfall expected
M
moderate heat & humidity
13
kph wind from NE

Koh Samui weather for Wednesday 17th December 2025

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 8 hours of bright sunshine. There are 5-10 mm of rainfall expected with 31% chance of some rain and a light breeze of 11 kph from the north-east.

30
°C maximum temperature
26
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
9
UV index (Very High)
31
% chance of some rain
<10
mm of rainfall expected
M
moderate heat & humidity
11
kph wind from NE

Koh Samui weather for Thursday 18th December 2025

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 6 hours of bright sunshine. There are 0-2 mm of rainfall expected with 63% chance of some rain and a light breeze of 10 kph from the north-east.

30
°C maximum temperature
26
°C minimum temperature
isolated thunderstorms
6
hours of sunshine
9
UV index (Very High)
63
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
10
kph wind from NE

Koh Samui weather for Friday 19th December 2025

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 7 hours of bright sunshine. There are 0-2 mm of rainfall expected with 41% chance of some rain and a gentle breeze of 14 kph from the north-east.

30
°C maximum temperature
26
°C minimum temperature
isolated thunderstorms
7
hours of sunshine
9
UV index (Very High)
41
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
14
kph wind from NE

Koh Samui weather for Saturday 20th December 2025

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 7 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 13 kph from the north-east.