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.

Monday
19th Jan
30

25

6

9
Tuesday
20th Jan
30

25

7

9
Wednesday
21st Jan
29

25

5

9
Thursday
22nd Jan
30

25

7

9
Friday
23rd Jan
30

26

6

9

5-day weather forecast updated at 04:03 on Saturday 17th January 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 Monday 19th January 2026

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 32% chance of some rain and a light breeze of 10 kph from the south-east.

30
°C maximum temperature
25
°C minimum temperature
isolated thunderstorms
6
hours of sunshine
9
UV index (Very High)
32
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
10
kph wind from SE

Koh Samui weather for Tuesday 20th January 2026

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 37% chance of some rain and a light breeze of 11 kph from the south-east.

30
°C maximum temperature
25
°C minimum temperature
isolated thunderstorms
7
hours of sunshine
9
UV index (Very High)
37
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
11
kph wind from SE

Koh Samui weather for Wednesday 21st January 2026

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 29°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 5 hours of bright sunshine. There are 0-2 mm of rainfall expected with 56% chance of some rain and a gentle breeze of 14 kph from the south-east.

29
°C maximum temperature
25
°C minimum temperature
isolated thunderstorms
5
hours of sunshine
9
UV index (Very High)
56
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
14
kph wind from SE

Koh Samui weather for Thursday 22nd January 2026

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 63% chance of some rain and a gentle breeze of 17 kph from the east.

30
°C maximum temperature
25
°C minimum temperature
isolated thunderstorms
7
hours of sunshine
9
UV index (Very High)
63
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
17
kph wind from E

Koh Samui weather for Friday 23rd January 2026

Expect sunshine and showers 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 2-5 mm of rainfall expected with 71% chance of some rain and a gentle breeze of 18 kph from the east.