Ko Samui weather by month

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

Temperature in Ko 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 Ko Samui29
29°C maximum daytime temperature in February in Ko Samui29
30°C maximum daytime temperature in March in Ko Samui30
32°C maximum daytime temperature in April in Ko Samui32
32°C maximum daytime temperature in May in Ko Samui32
31°C maximum daytime temperature in June in Ko Samui31
31°C maximum daytime temperature in July in Ko Samui31
31°C maximum daytime temperature in August in Ko Samui31
31°C maximum daytime temperature in September in Ko Samui31
30°C maximum daytime temperature in October in Ko Samui30
29°C maximum daytime temperature in November in Ko Samui29
29°C maximum daytime temperature in December in Ko Samui29
Min temperature (night-time)
22°C minimum night-time temperature in January in Ko Samui22
23°C minimum night-time temperature in February in Ko Samui23
24°C minimum night-time temperature in March in Ko Samui24
25°C minimum night-time temperature in April in Ko Samui25
25°C minimum night-time temperature in May in Ko Samui25
24°C minimum night-time temperature in June in Ko Samui24
24°C minimum night-time temperature in July in Ko Samui24
24°C minimum night-time temperature in August in Ko Samui24
24°C minimum night-time temperature in September in Ko Samui24
23°C minimum night-time temperature in October in Ko Samui23
23°C minimum night-time temperature in November in Ko Samui23
22°C minimum night-time temperature in December in Ko Samui22
Heat & Humidity
High heat & humidity in January in Ko SamuiH
High heat & humidity in February in Ko SamuiH
Very high heat & humidity in March in Ko SamuiVH
Very high heat & humidity in April in Ko SamuiVH
Very high heat & humidity in May in Ko SamuiVH
Very high heat & humidity in June in Ko SamuiVH
Very high heat & humidity in July in Ko SamuiVH
Very high heat & humidity in August in Ko SamuiVH
Very high heat & humidity in September in Ko SamuiVH
High heat & humidity in October in Ko SamuiH
High heat & humidity in November in Ko SamuiH
High heat & humidity in December in Ko SamuiH
Sea temperature
28°C sea temperature in January in Ko Samui28
28°C sea temperature in February in Ko Samui28
29°C sea temperature in March in Ko Samui29
30°C sea temperature in April in Ko Samui30
30°C sea temperature in May in Ko Samui30
30°C sea temperature in June in Ko Samui30
29°C sea temperature in July in Ko Samui29
29°C sea temperature in August in Ko Samui29
29°C sea temperature in September in Ko Samui29
29°C sea temperature in October in Ko Samui29
28°C sea temperature in November in Ko Samui28
28°C sea temperature in December in Ko Samui28

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

Sunshine & Daylight in Ko 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 Ko Samui12
12 hours of daylight per day in February in Ko Samui12
12 hours of daylight per day in March in Ko Samui12
12 hours of daylight per day in April in Ko Samui12
13 hours of daylight per day in May in Ko Samui13
13 hours of daylight per day in June in Ko Samui13
13 hours of daylight per day in July in Ko Samui13
12 hours of daylight per day in August in Ko Samui12
12 hours of daylight per day in September in Ko Samui12
12 hours of daylight per day in October in Ko Samui12
12 hours of daylight per day in November in Ko Samui12
12 hours of daylight per day in December in Ko Samui12
UV Index (Maximum)
UV (maximum) index 11 (Extreme) in January in Ko Samui11
UV (maximum) index 11+ (Extreme) in February in Ko Samui11
UV (maximum) index 11+ (Extreme) in March in Ko Samui11
UV (maximum) index 11+ (Extreme) in April in Ko Samui11
UV (maximum) index 11+ (Extreme) in May in Ko Samui11
UV (maximum) index 11+ (Extreme) in June in Ko Samui11
UV (maximum) index 11+ (Extreme) in July in Ko Samui11
UV (maximum) index 11+ (Extreme) in August in Ko Samui11
UV (maximum) index 11+ (Extreme) in September in Ko Samui11
UV (maximum) index 11+ (Extreme) in October in Ko Samui11
UV (maximum) index 11 (Extreme) in November in Ko Samui11
UV (maximum) index 10 (Very High) in December in Ko Samui10

Rainfall in Ko 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 Ko Samui10
5 days with some rainfall in February in Ko Samui5
5 days with some rainfall in March in Ko Samui5
8 days with some rainfall in April in Ko Samui8
17 days with some rainfall in May in Ko Samui17
16 days with some rainfall in June in Ko Samui16
17 days with some rainfall in July in Ko Samui17
17 days with some rainfall in August in Ko Samui17
17 days with some rainfall in September in Ko Samui17
20 days with some rainfall in October in Ko Samui20
19 days with some rainfall in November in Ko Samui19
13 days with some rainfall in December in Ko Samui13
Average monthly rainfall (mm)
123 mm monthly rainfall in January in Ko Samui123
39 mm monthly rainfall in February in Ko Samui39
54 mm monthly rainfall in March in Ko Samui54
85 mm monthly rainfall in April in Ko Samui85
172 mm monthly rainfall in May in Ko Samui172
118 mm monthly rainfall in June in Ko Samui118
146 mm monthly rainfall in July in Ko Samui146
137 mm monthly rainfall in August in Ko Samui137
141 mm monthly rainfall in September in Ko Samui141
275 mm monthly rainfall in October in Ko Samui275
463 mm monthly rainfall in November in Ko Samui463
188 mm monthly rainfall in December in Ko Samui188

More about Ko Samui

Ko Samui by month

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

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The climate guide for Thailand (Ko 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 Ko Samui?

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

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

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Tropical storm risk: Ko 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 Ko Samui with the USA

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

Maximum daytime temperature (°C)

Ko 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)

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