Ko Samui Weather in September

What's the weather like in Ko Samui (Surat Thani) in September 2024?

The climate in Ko Samui during September can be summarized as hot, humid and wet.

September is in the fall / autumn in Ko Samui and is typically the 6th warmest month of the year. Daytime maximum temperatures average around a steamy 31°C (87°F), whilst at night 24°C (75°F) is normal.

Ko Samui weather averages (imperial / metric)
Daytime temperature 30.8°C 87.4°F
Nightly temperature 23.6°C 74.5°F
Average temperature 27.2°C 81°F
Daily sunshine 5.9 hrs
Avg rainfall 141 mm 5.5 ins
Rainy days 17 days
Sea temperature 29.1°C 84.4°F
Humidity 78%
Windspeed 7.2kph 5 mph

On average September is the 6th wettest month of the year in Ko Samui with around 141mm 5.5 inches of rain making it a wet time to visit. This rainfall is typically spread over 17 days, although this may vary considerably.

On the flip side this corresponds to an average of 5.9 hours of sunshine per day.

September temperatures in Ko Samui

Ko Samui average temperature in September

September rainfall

Ko Samui average rain in September

September hourly sunshine

Ko Samui average rain in September

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Ko Samui in September 2024.

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
Map showing location of Ko Samui (9.53567, 99.93567) Ko Samui map pin © Google

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