Koh Samui weather live forecast

Today's maximum temperature in Koh Samui is expected to be 88°F. Select a day from the live weather forecast for Koh Samui, Thailand for more weather parameters.

Sunday
28th Dec
88

79

5

9
Monday
29th Dec
90

79

7

9
Tuesday
30th Dec
88

79

7

10
Wednesday
31st Dec
90

79

7

10
Thursday
1st Jan
88

79

6

10

5-day weather forecast updated at 04:01 on Saturday 27th 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 Sunday 28th December 2025

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 88°F, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 5 hours of bright sunshine. There are 2-5 mm of rainfall expected with 48% chance of some rain and a gentle breeze of 8 mph from the east.

88
°F maximum temperature
79
°F minimum temperature
isolated thunderstorms
5
hours of sunshine
9
UV index (Very High)
48
% chance of some rain
<5
mm of rainfall expected
M
moderate heat & humidity
8
mph wind from E

Koh Samui weather for Monday 29th December 2025

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 90°F, 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 light breeze of 7 mph from the north-east.

90
°F maximum temperature
79
°F minimum temperature
scattered clouds
7
hours of sunshine
9
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
7
mph wind from NE

Koh Samui weather for Tuesday 30th December 2025

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 88°F, moderate levels of heat & humidity, maximum UV of 10 (Very High) and 7 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 6 mph from the north-east.

88
°F maximum temperature
79
°F minimum temperature
scattered clouds
7
hours of sunshine
10
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
6
mph wind from NE

Koh Samui weather for Wednesday 31st December 2025

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 90°F, moderate levels of heat & humidity, maximum UV of 10 (Very High) and 7 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 6 mph from the north-east.

90
°F maximum temperature
79
°F minimum temperature
scattered clouds
7
hours of sunshine
10
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
6
mph wind from NE

Koh Samui weather for Thursday 1st January 2026

Expect broken clouds in Koh Samui, Thailand with a maximum temperature of 88°F, moderate levels of heat & humidity, maximum UV of 10 (Very High) and 6 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 7 mph from the east.