Koh Samui weather by month

Check out Koh Samui weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature in Koh Samui (°C)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
29°C maximum daytime temperature in January in Koh Samui29
29°C maximum daytime temperature in February in Koh Samui29
30°C maximum daytime temperature in March in Koh Samui30
32°C maximum daytime temperature in April in Koh Samui32
32°C maximum daytime temperature in May in Koh Samui32
31°C maximum daytime temperature in June in Koh Samui31
31°C maximum daytime temperature in July in Koh Samui31
31°C maximum daytime temperature in August in Koh Samui31
31°C maximum daytime temperature in September in Koh Samui31
30°C maximum daytime temperature in October in Koh Samui30
29°C maximum daytime temperature in November in Koh Samui29
29°C maximum daytime temperature in December in Koh Samui29
Min temperature (night-time)
22°C minimum night-time temperature in January in Koh Samui22
23°C minimum night-time temperature in February in Koh Samui23
24°C minimum night-time temperature in March in Koh Samui24
25°C minimum night-time temperature in April in Koh Samui25
25°C minimum night-time temperature in May in Koh Samui25
24°C minimum night-time temperature in June in Koh Samui24
24°C minimum night-time temperature in July in Koh Samui24
24°C minimum night-time temperature in August in Koh Samui24
24°C minimum night-time temperature in September in Koh Samui24
23°C minimum night-time temperature in October in Koh Samui23
23°C minimum night-time temperature in November in Koh Samui23
22°C minimum night-time temperature in December in Koh Samui22
Heat & Humidity
High heat & humidity in January in Koh SamuiH
High heat & humidity in February in Koh SamuiH
Very high heat & humidity in March in Koh SamuiVH
Very high heat & humidity in April in Koh SamuiVH
Very high heat & humidity in May in Koh SamuiVH
Very high heat & humidity in June in Koh SamuiVH
Very high heat & humidity in July in Koh SamuiVH
Very high heat & humidity in August in Koh SamuiVH
Very high heat & humidity in September in Koh SamuiVH
High heat & humidity in October in Koh SamuiH
High heat & humidity in November in Koh SamuiH
High heat & humidity in December in Koh SamuiH
Sea temperature
28°C sea temperature in January in Koh Samui28
28°C sea temperature in February in Koh Samui28
29°C sea temperature in March in Koh Samui29
30°C sea temperature in April in Koh Samui30
30°C sea temperature in May in Koh Samui30
30°C sea temperature in June in Koh Samui30
29°C sea temperature in July in Koh Samui29
29°C sea temperature in August in Koh Samui29
29°C sea temperature in September in Koh Samui29
29°C sea temperature in October in Koh Samui29
28°C sea temperature in November in Koh Samui28
28°C sea temperature in December in Koh Samui28

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & Daylight in Koh Samui

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daily hours of sunshine
Daily hours of daylight
12 hours of daylight per day in January in Koh Samui12
12 hours of daylight per day in February in Koh Samui12
12 hours of daylight per day in March in Koh Samui12
12 hours of daylight per day in April in Koh Samui12
13 hours of daylight per day in May in Koh Samui13
13 hours of daylight per day in June in Koh Samui13
13 hours of daylight per day in July in Koh Samui13
12 hours of daylight per day in August in Koh Samui12
12 hours of daylight per day in September in Koh Samui12
12 hours of daylight per day in October in Koh Samui12
12 hours of daylight per day in November in Koh Samui12
12 hours of daylight per day in December in Koh Samui12
UV Index (Maximum)
UV (maximum) index 11 (Extreme) in January in Koh Samui11
UV (maximum) index 11+ (Extreme) in February in Koh Samui11
UV (maximum) index 11+ (Extreme) in March in Koh Samui11
UV (maximum) index 11+ (Extreme) in April in Koh Samui11
UV (maximum) index 11+ (Extreme) in May in Koh Samui11
UV (maximum) index 11+ (Extreme) in June in Koh Samui11
UV (maximum) index 11+ (Extreme) in July in Koh Samui11
UV (maximum) index 11+ (Extreme) in August in Koh Samui11
UV (maximum) index 11+ (Extreme) in September in Koh Samui11
UV (maximum) index 11+ (Extreme) in October in Koh Samui11
UV (maximum) index 11 (Extreme) in November in Koh Samui11
UV (maximum) index 10 (Very High) in December in Koh Samui10

Rainfall in Koh Samui

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of days with some rain
10 days with some rainfall in January in Koh Samui10
5 days with some rainfall in February in Koh Samui5
5 days with some rainfall in March in Koh Samui5
8 days with some rainfall in April in Koh Samui8
17 days with some rainfall in May in Koh Samui17
16 days with some rainfall in June in Koh Samui16
17 days with some rainfall in July in Koh Samui17
17 days with some rainfall in August in Koh Samui17
17 days with some rainfall in September in Koh Samui17
20 days with some rainfall in October in Koh Samui20
19 days with some rainfall in November in Koh Samui19
13 days with some rainfall in December in Koh Samui13
Average monthly rainfall (mm)
123 mm monthly rainfall in January in Koh Samui123
39 mm monthly rainfall in February in Koh Samui39
54 mm monthly rainfall in March in Koh Samui54
85 mm monthly rainfall in April in Koh Samui85
172 mm monthly rainfall in May in Koh Samui172
118 mm monthly rainfall in June in Koh Samui118
146 mm monthly rainfall in July in Koh Samui146
137 mm monthly rainfall in August in Koh Samui137
141 mm monthly rainfall in September in Koh Samui141
275 mm monthly rainfall in October in Koh Samui275
463 mm monthly rainfall in November in Koh Samui463
188 mm monthly rainfall in December in Koh Samui188

More about Koh Samui

Koh Samui by month

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

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The climate guide for Thailand (Koh Samui) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Koh Samui?

Koh Samui has a hot tropical climate with a short dry season.

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

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Tropical storm risk: Koh Samui, Thailand typhoon season

% of month affected by tropical storms
0
0
0
0
0
0
0
0
0
1.2%
2.2%
<1%
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

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More about Thailand

Compare Koh Samui with the USA

Below the Koh Samui chart shows average maximum daytime temperature for Koh Samui, Thailand and the USA (Washington).

Maximum daytime temperature (°C)

Koh Samui, Thailand
USA (Washington)
29
5
29
7
30
13
32
19
32
24
31
29
31
31
31
30
31
26
30
20
29
14
29
8
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

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

Compare more Koh Samui weather >>

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