Koh Samui in september: average Weather, Temperature and Climate, Where to go?
Weather on the island of Koh Samui in september 2025
Below, check out the weather forecast for the month of september for most popular cities in Ko Samui. These predictions are statistics for september from weather reports for over 10 years. The percentage indicates the probability of having the weather mentioned.
Average weather in september in Chaweng Beach
tolerable weather UV index: 7
Weather at 6am
83°F
Partly Cloudy
39% of time
25%
20%
10%
Weather at 12pm
85°F
Partly Cloudy
37% of time
32%
17%
10%
Weather at 6pm
85°F
Partly Cloudy
38% of time
23%
18%
15%
Weather at 3am
85°F
35%
31%
18%
10%
More information about the weather in Chaweng Beach in september
Where to go on the island of Koh Samui in september?
Where to go on the island of Koh Samui in september: destination map
perfect weather
good
tolerable
bad
very bad
Where should you go on the island of Koh Samui in september when it comes to the weather?
Remember:
The climate on the island of Koh Samui in september is tolerable across the board.
You are lucky: Although it is not perfect the weather in Ko Samui in september should be pretty good in Bophut, Koh Madsum, Lamai beach, Chaweng Beach, Lipa Noi, Maenam, Koh Taen and Koh Phaluai. I allows to savor vacation in these places. And even why not take a little time to enjoy the hotel pool!
If you do not go lazing in the sun, but, for example for hiking, the cities of Bang Kao (Laem Sor beach), Choeng Mon and Nathon have a quite correct weather for it in september.
Climate on the island of Koh Samui in september
Climate in Chaweng Beach in september
In the month of september, the mean temperature in Chaweng Beach is 85°F (maximum temperature is 86°F and minimum temperature is 83°F). The climate is nice there in this month. With 7.4in over 12 days, you will experience some showers during your vacations. But this is rather reasonably and it is only of temporary showers.
With good weather conditions, september is a good time to go in Chaweng Beach.
| September | |||
| Average temperature | 85°F | ||
| Highest temperature | 86°F | ||
| Lowest temperature | 83°F | ||
| Sea temperature | 85°F | ||
| Rainfall | 7.4in | ||
| Number of days with rainfall | 12 day(s) (41%) | ||
| Humidity | 78% | ||
| Daily sunshine hours | 11 | ||
| Cloud cover | 43% | ||
| Length of day | 12:11 | ||
| Our opinion at whereandwhen.net | tolerable |
Climate in Bang Kao (Laem Sor beach) in september
In the month of september, maximum temperature is 86°F and minimum temperature is 83°F (for an average temperature of 85°F). The climate is quite enjoyable in this location in this month. With 7.4in over 12 days, rainfall can happen during your trip. But this is pretty reasonably and you will not be too bothered by it.
With a correct weather, september is okay (but not the best month) for traveling in this city.
| September | |||
| Average temperature | 85°F | ||
| Highest temperature | 86°F | ||
| Lowest temperature | 83°F | ||
| Sea temperature | 85°F | ||
| Rainfall | 7.4in | ||
| Number of days with rainfall | 12 day(s) (41%) | ||
| Humidity | 78% | ||
| Daily sunshine hours | 11 | ||
| Cloud cover | 43% | ||
| Length of day | 12:10 | ||
| Our opinion at whereandwhen.net | tolerable |
Climate in Bophut in september
In september, maximum temperature is 86°F and minimum temperature is 83°F (for an average temperature of 85°F). The climate is comfortable there in the month of september. With 7.4in over 12 days, you risk getting wet slightly for your vacations. But this is rather moderate and it will not be continuous.
With a good climate, the month of september is a recommended month to go in Bophut in Ko Samui.
| September | |||
| Average temperature | 85°F | ||
| Highest temperature | 86°F | ||
| Lowest temperature | 83°F | ||
| Sea temperature | 85°F | ||
| Rainfall | 7.4in | ||
| Number of days with rainfall | 12 day(s) (41%) | ||
| Humidity | 78% | ||
| Daily sunshine hours | 11 | ||
| Cloud cover | 43% | ||
| Length of day | 12:10 | ||
| Our opinion at whereandwhen.net | tolerable |
Climate in Choeng Mon in september
In september, the mean temperature in Choeng Mon is 85°F (maximum temperature is 86°F and minimum temperature is 83°F). The climate is quite enjoyable around this city in this month. With 7.4in over 12 days, rainfall can happen throughout your holidays. But this is rather moderate and it will not be continuous.
With a correct climate, the month of september is okay (but not the best time) for traveling in that area in Ko Samui.
| September | |||
| Average temperature | 85°F | ||
| Highest temperature | 86°F | ||
| Lowest temperature | 83°F | ||
| Sea temperature | 85°F | ||
| Rainfall | 7.4in | ||
| Number of days with rainfall | 12 day(s) (41%) | ||
| Humidity | 78% | ||
| Daily sunshine hours | 11 | ||
| Cloud cover | 43% | ||
| Length of day | 12:11 | ||
| Our opinion at whereandwhen.net | tolerable |
Climate in Koh Madsum in september
In the month of september, maximum temperature is 86°F and minimum temperature is 83°F (for an average temperature of 85°F). The climate is quite pleasant in this city in september. With 7.4in over 12 days, you risk getting wet slightly for your trip. But this is reasonably and you will not be too bothered by it.
With a good climate, the month of september is a recommended month to go in this locality in Ko Samui.
| September | |||
| Average temperature | 85°F | ||
| Highest temperature | 86°F | ||
| Lowest temperature | 83°F | ||
| Sea temperature | 85°F | ||
| Rainfall | 7.4in | ||
| Number of days with rainfall | 12 day(s) (41%) | ||
| Humidity | 78% | ||
| Daily sunshine hours | 11 | ||
| Cloud cover | 43% | ||
| Length of day | 12:10 | ||
| Our opinion at whereandwhen.net | tolerable |
All cities on the island of Koh Samui in september
| Chaweng Beach in september | tolerable weather |
| Bang Kao (Laem Sor beach) in september | tolerable weather |
| Bophut in september | tolerable weather |
| Choeng Mon in september | tolerable weather |
| Koh Madsum in september | tolerable weather |
| Koh Phaluai in september | tolerable weather |
| Koh Taen in september | tolerable weather |
| Lamai beach in september | tolerable weather |
| Lipa Noi in september | tolerable weather |
| Maenam in september | tolerable weather |
| Nathon in september | tolerable weather |
Weather data for Koh Samui in september:
Weather data for Koh Samui in september is derived from an average of the weather forecast since 2009 on the island of Koh Samui. There is a margin of error and these forecasts are to be considered as general information only. The weather on the island of Koh Samui can vary slightly from year to year, but these predictions should limit surprises. So you can pack your bags and check when is the best time to go to Koh Samui.