Koh Samui weather live forecast

Today's maximum temperature in Koh Samui is expected to be 30°C. Select a day from the live weather forecast for Koh Samui, Thailand for more weather parameters.

Tuesday
17th Mar
30

27

7

11
Wednesday
18th Mar
30

26

6

11
Thursday
19th Mar
31

26

7

11
Friday
20th Mar
31

26

8

11
Saturday
21st Mar
31

26

7

11

5-day weather forecast updated at 04:01 on Tuesday 17th March 2026 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 17th March 2026

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 11+ (Extreme) and 7 hours of bright sunshine. There are 2-5 mm of rainfall expected with 54% chance of some rain and a moderate breeze of 23 kph from the south-east.

30
°C maximum temperature
27
°C minimum temperature
isolated thunderstorms
7
hours of sunshine
11
UV index (Extreme)
54
% chance of some rain
<5
mm of rainfall expected
M
moderate heat & humidity
23
kph wind from SE

Koh Samui weather for Wednesday 18th March 2026

Expect broken clouds in Koh Samui, Thailand with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 11 (Extreme) and 6 hours of bright sunshine. There are 0 mm of rainfall expected and a moderate breeze of 20 kph from the south-east.

30
°C maximum temperature
26
°C minimum temperature
broken clouds
6
hours of sunshine
11
UV index (Extreme)
0
mm of rainfall expected
M
moderate heat & humidity
20
kph wind from SE

Koh Samui weather for Thursday 19th March 2026

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 11+ (Extreme) and 7 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 17 kph from the south-east.

31
°C maximum temperature
26
°C minimum temperature
scattered clouds
7
hours of sunshine
11
UV index (Extreme)
0
mm of rainfall expected
M
moderate heat & humidity
17
kph wind from SE

Koh Samui weather for Friday 20th March 2026

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 11+ (Extreme) and 8 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 18 kph from the south-east.

31
°C maximum temperature
26
°C minimum temperature
scattered clouds
8
hours of sunshine
11
UV index (Extreme)
0
mm of rainfall expected
M
moderate heat & humidity
18
kph wind from SE

Koh Samui weather for Saturday 21st March 2026

Expect broken clouds in Koh Samui, Thailand with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 11+ (Extreme) and 7 hours of bright sunshine. There are 0 mm of rainfall expected and a moderate breeze of 20 kph from the south-east.