Koh Samui weather live forecast

Today's maximum temperature in Koh Samui is expected to be 84°F. Select a day from the live weather forecast for Koh Samui, Thailand for more weather parameters.

Monday
16th Mar
84

81

5

11
Tuesday
17th Mar
86

81

5

11
Wednesday
18th Mar
88

81

6

11
Thursday
19th Mar
88

81

8

11
Friday
20th Mar
88

81

9

11

5-day weather forecast updated at 04:01 on Sunday 15th March 2026 GMT

More about Koh Samui

Koh Samui by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for Thailand

TUI: Top deals & discounts on 2026/2027 holidays

Sale

Explore latest special offers & online deals from TUI
Free child places & £0 deposits with direct debit available
Book summer & winter sun holidays in 2026/2027

Go to TUI deal >>

View all TUI offers

TUI deal finder

Destination

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 16th March 2026

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 84°F, moderate levels of heat & humidity, maximum UV of 11 (Extreme) and 5 hours of bright sunshine. There are 2-5 mm of rainfall expected with 83% chance of some rain and a moderate breeze of 12 mph from the east.

84
°F maximum temperature
81
°F minimum temperature
isolated thunderstorms
5
hours of sunshine
11
UV index (Extreme)
83
% chance of some rain
<5
mm of rainfall expected
M
moderate heat & humidity
12
mph wind from E

Koh Samui weather for Tuesday 17th March 2026

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 86°F, moderate levels of heat & humidity, maximum UV of 11 (Extreme) and 5 hours of bright sunshine. There are 0-2 mm of rainfall expected with 60% chance of some rain and a moderate breeze of 12 mph from the south-east.

86
°F maximum temperature
81
°F minimum temperature
isolated thunderstorms
5
hours of sunshine
11
UV index (Extreme)
60
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
12
mph wind from SE

Koh Samui weather for Wednesday 18th March 2026

Expect isolated thunderstorms in Koh Samui, Thailand with a maximum temperature of 88°F, moderate levels of heat & humidity, maximum UV of 11+ (Extreme) and 6 hours of bright sunshine. There are 0-2 mm of rainfall expected with 44% chance of some rain and a moderate breeze of 13 mph from the south-east.

88
°F maximum temperature
81
°F minimum temperature
isolated thunderstorms
6
hours of sunshine
11
UV index (Extreme)
44
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
13
mph wind from SE

Koh Samui weather for Thursday 19th March 2026

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 88°F, 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 11 mph from the south-east.

88
°F maximum temperature
81
°F minimum temperature
scattered clouds
8
hours of sunshine
11
UV index (Extreme)
0
mm of rainfall expected
M
moderate heat & humidity
11
mph wind from SE

Koh Samui weather for Friday 20th March 2026

Expect scattered clouds in Koh Samui, Thailand with a maximum temperature of 88°F, moderate levels of heat & humidity, maximum UV of 11 (Extreme) and 9 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 12 mph from the south-east.