Ko Samui monthly weather averages

Average daytime temperature

The bar chart below shows the average monthly peak daytime temperatures at Ko Samui

Ko Samui average temperature chart (Celsius) Ko Samui average temperature chart (Fahrenheit)
Average monthly temperatures in Ko Samui (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 28.4 29.1 30.2 31.6 31.8 31.3 31 30.9 30.6 29.9 28.7 28.4
°F 83.2 84.3 86.4 88.8 89.2 88.3 87.8 87.6 87.1 85.8 83.7 83

Please note: these are the average peak daytime temperatures (usually around mid-afternoon) so do not show daytime / night highs and lows. To see the daily range of temperatures have a look at the temperature max / min chart below.

Average rainfall & rainy days

The graph below shows the average rainfall and number of rainy days per month.

Ko Samui monthly rainfall chart (mm) Ko Samui monthly rainfall chart (inches)
Average monthly rainfall in Ko Samui (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 123 39 54 85 172 118 146 137 141 275 463 188
inches 4.8 1.5 2.1 3.3 6.8 4.6 5.7 5.4 5.5 10.8 18.2 7.4
Rainy days 10 5 5 8 17 16 17 17 17 20 19 13

Average daily sunshine

The bar chart below shows the average daily sunshine hours in Ko Samui

Ko Samui average daily sunshine chart
Average daily sunshine Ko Samui
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Hrs sunshine 7.6 8.7 8.7 8.3 6.7 6 6.2 5.9 5.9 6.2 6.2 7

Day / night temperatures

The graph below shows the daily range of temperatures for each month.

Ko Samui average minimum / maximum temperatures (Celsius) Ko Samui average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Ko Samui (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 22.2 23.4 24 24.7 24.5 24.4 23.9 24 23.6 23.4 22.8 22.3
Max °C 28.6 29.2 30.4 31.8 32 31.5 31.2 31.1 30.8 30.1 28.9 28.5
Min °F 72 74.1 75.2 76.4 76 75.8 74.9 75.1 74.5 74 73 72.1
Max °F 77.7 79.3 81 82.8 82.8 82.2 81.5 81.5 81 80.1 78.4 77.7

Sea temperature

The graph below shows the average sea temperature.

Ko Samui average sea temperature chart (Celsius) Ko Samui average sea temperature chart (Fahrenheit)
Average sea temperature around Ko Samui in degrees centigrade and fahrenheit
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 28 28.4 29.1 30 30.2 29.8 29.5 29.3 29.1 29.1 28.9 28.3
°F 82.4 83.1 84.3 85.9 86.4 85.7 85.1 84.7 84.4 84.3 84.1 83

Wind speed

The graph below shows the average wind speed.

Ko Samui average winspeed by month (km/h) Ko Samui average winspeed by month (mph)
Average wind speed in Ko Samui (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 10 10 9 7 7 9 9 9 7 5 7 9
mph 6 7 6 5 4 6 5 6 5 3 5 6

A monthly average windspeed of over 16km/h or 10mph suggests a location is fairly windy.

Relative humidity

The graph below shows the average relative humidity.

Ko Samui relative humidity averages
Average relative humidity in Ko Samui
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
79% 79% 78% 78% 78% 77% 77% 78% 78% 83% 83% 80%
Ko Samui

Other monthly averages

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Ko Samui weather stats

Ko Samui weather statistics
Hottest month: April 31.6°C 88.9°F
Driest month: February 39mm 1.5ins
Sunniest month: February 8.7hrs
Coldest month: January 28.4°C 83.1°F
Wettest month: November 463mm 18.2ins
Warmest sea: May 30.2°C 86.4°F
Map showing location of Ko Samui (9.53567, 99.93567)

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