Ko Samui weather in September 2021

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  • 31°C maximum daytime temperature in September in Ko Samui31
    31°C max day temperature
  • 6 hours of sunshine per day
  • 17 days with some rainfall in September in Ko Samui17
    17 days with some rainfall
  • 24°C minimum night-time temperature in September in Ko Samui24
    24°C min night temperature
  • 12 hours of daylight per day in September in Ko Samui12
    12 hours of daylight per day
  • Very high heat & humidity in September in Ko SamuiVH
    Very High heat & humidity
  • 141 mm monthly rainfall in September in Ko Samui141
    141 mm of monthly rainfall
  • UV (maximum) index 11+ (Extreme) in September in Ko Samui11
    11+ (Extreme) UV index
  • 29°C sea temperature in September in Ko Samui29
    29°C sea temperature

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The September weather guide for Ko Samui, Thailand shows long term 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.

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How hot is it in Ko Samui in September?

Daytime temperatures usually reach 31°C in Ko Samui in September with very high heat and humidity, falling to 24°C at night.

How sunny is it in Ko Samui in September?

There are normally 6 hours of bright sunshine each day in Ko Samui in September - that's 47% of daylight hours.

How warm is the sea around Ko Samui in September?

The average sea temperature around Ko Samui in September is 29°C.

Does it rain in Ko Samui in September?

There are usually 17 days with some rain in Ko Samui in September and the average monthly rainfall is 141mm.

Ko Samui sunrise & sunset times for September 2021

Browse the sunrise & sunset times for Ko Samui in September 2021. Select a month to view Ko Samui sunrise & sunset times for the next twelve months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Wednesday, 1st September 2021 06:11 18:29
Wednesday, 15th September 2021 06:10 18:20
Thursday, 30th September 2021 06:08 18:11
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Metric (°C / mm)  |  Imperial (°F / inches)

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Where is hot in Thailand in September for 2021/2022?

Below are average maximum temperatures at popular destinations in Thailand in September. Select a destination to see more weather parameters.

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