Which is the hottest month in Koh Samui?

The hottest time of year in Koh Samui is normally April. Expect maximum daytime temperatures to reach 32°C with very high heat and humidity.

Which month has the most rain in Koh Samui?

In terms of rainfall, November is usually the wettest month in Koh Samui with 463mm on average. There are normally 19 days in November with some rain.

When is it sunniest in Koh Samui?

The sunniest time of year in Koh Samui is normally February with bright sunshine on average for 72% of daylight hours; that's 9 hours of sunshine per day.

When is the sea warmest in Koh Samui?

The sea is usually at its warmest in Koh Samui in May when the water temperature reaches 30°C.

Best time to visit Koh Samui

Q: When is the best time to visit Koh Samui?

The best time to visit Koh Samui is February based on the following average weather conditions. Maximum daytime temperature = 22 - 30°C. Daily hours of sunshine = 10 hours or more.

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Koh Samui by month

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

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Destination

When is the best time to visit Koh Samui?

The best time to visit Koh Samui is February based on the following average weather conditions.

Maximum daytime temperature = 22 - 30°C [remove]
Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

4
Jan
4
Feb
4
Mar
3
Apr
2
May
2.5
Jun
2.5
Jul
2.5
Aug
2.5
Sep
3
Oct
3.5
Nov
3.5
Dec

Change criteria

Max Day Temperature (°C)

29
Jan
29
Feb
30
Mar
32
Apr
32
May
31
Jun
31
Jul
31
Aug
31
Sep
30
Oct
29
Nov
29
Dec

Hours of Sunshine (daily)

7
Jan
9
Feb
8
Mar
8
Apr
6
May
6
Jun
6
Jul
6
Aug
6
Sep
6
Oct
6
Nov
6
Dec

Best time to visit

Destination

Daytime temperature

Sunshine hours

Sea temperature

Monthly rainfall

Days with some rain

Heat & humidity

The weather guide for Thailand (Koh Samui) shows long term weather averages processed from data supplied by CRU (University of East Anglia) & today's weather forecast provided by meteoblue. Find out more about our data sources.

Metric (°C / mm) | Imperial (°F / inches)