Koh Samui, THAILAND and its best beaches
Climate - Temperatures and rainfall - South China Sea
Koh Samui: Temperatures during the day, at night, rain and bathing conditions
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Thailand : climate and when to go to Koh samui
The climate in Phuket and Koh Samui is very pleasant throughout the year, with temperatures varying between 77°F at night and 93°F during the day.
There are three seasons, the hot season from February to May, the rainy season from the end of September to November, and the "cool" season from October to January.
From February to October it average 32 to 38 degrees, but from July to September there may be some showers, but only for a few hours. The rainy season is often summed up in some "refreshing" tropical rain showers followed by the return of the sun. The climate is tropical so very wet throughout the year, but Samui always remains refreshed with a pleasant sea breeze coming from the Gulf.
January Acceptable |
February Pecfect |
March Pecfect |
April Pecfect |
May Risky |
June Acceptable |
July Acceptable |
August Acceptable |
September Acceptable |
October Avoid |
November Avoid |
December Risky |
When to go? The hottest month for the beach, lazing around and swimming is April. Check the precipitations because showers are possible but the sun returns quickly, otherwise other periods are possible. The coolest month is January, if you can not stand the heat too much. The driest month of the year is February, if you do not like the rain at all.
Click on
Phuket -
Koh Samui to display its climate.
Graphs and temperature curves with average precipitation over the year


Precipitation, rainfall, cyclone: THAILAND

Temperatures of bathing water around Koh Samui

Landmarks







No cyclone risk for this country


South China Sea
Climate September 2023
Koh Samui sunshine in summer and winter



The sun at its zenith, that means well perpendicular to the surface of the Earth, sending 100% of radiation and heat. Koh Samui receives in winter (january), 83% of sun power and 97% during summer time (july).
The average temperature and sunshine deviations between summer and winter are 14%. This small gap means that the temperature at sea does not really vary and that the sea remains warm enough in summer and winter. The air is also hot all year round without great thermal amplitude.

Average temperatures and rainfall for a stay in September
On the left, the averages observed every month of September on the Thailand beaches. The trends for next month are, slightly lower average daytime temperatures, a bathing water in South China Sea remaining at a stable temperature, more abundant rains with nights as temperate as this month.
Sunset and sunrise times for THAILAND
Local time : September 2023, Saturday 30, 10:32 AM
Sunrise time : 06:10 am, point A
Sunset time : 6:08 pm, point B
Duration of daylight : 11:58 / 24:00
Jet lag : GMT+7

The average monthly UV index of THAILAND
What is the period of mosquitoes virulence over the year?
Weather forecast for Koh Samui
Here are the current 5-day forecasts for Ban Bang Rak / Koh Samui. Temperatures are spaced 3 hours apart for each day. The summary of the state of the sky gives the trend of the week. The sea temperature at is a monthly average. In lagoons or seashores where the bathing water is shallow, you can add some degrees.
Sunday
October 01, 2023
8 am
82.7°F
29°C

Overcast clouds
Humidity 69%
Sea 85°F/29°C
Sunday
October 01, 2023
11 am
83.5°F
29°C

Overcast clouds
Humidity 65%
Sea 85°F/29°C
Sunday
October 01, 2023
2 pm
84.3°F
30°C

Light rain
Humidity 70%
Sea 85°F/29°C
Sunday
October 01, 2023
5 pm
83.9°F
29°C

Light rain
Humidity 77%
Sea 85°F/29°C
Sunday
October 01, 2023
8 pm
83.2°F
29°C

Light rain
Humidity 76%
Sea 85°F/29°C
Sunday
October 01, 2023
11 pm
82.2°F
28°C

Light rain
Humidity 75%
Sea 85°F/29°C
Monday
October 02, 2023
8 am
82.6°F
29°C

Light rain
Humidity 74%
Sea 85°F/29°C
Monday
October 02, 2023
11 am
82.9°F
29°C

Light rain
Humidity 72%
Sea 85°F/29°C
Monday
October 02, 2023
2 pm
83°F
29°C

Light rain
Humidity 75%
Sea 85°F/29°C
Monday
October 02, 2023
5 pm
82.6°F
29°C

Moderate rain
Humidity 77%
Sea 85°F/29°C
Monday
October 02, 2023
8 pm
83.1°F
29°C

Light rain
Humidity 75%
Sea 85°F/29°C
Monday
October 02, 2023
11 pm
81.6°F
28°C

Moderate rain
Humidity 78%
Sea 85°F/29°C
Tuesday
October 03, 2023
8 am
80.8°F
28°C

Light rain
Humidity 80%
Sea 85°F/29°C
Tuesday
October 03, 2023
11 am
81.7°F
28°C

Overcast clouds
Humidity 78%
Sea 85°F/29°C
Tuesday
October 03, 2023
2 pm
82.7°F
29°C

Overcast clouds
Humidity 77%
Sea 85°F/29°C
Tuesday
October 03, 2023
5 pm
82.7°F
29°C

Light rain
Humidity 77%
Sea 85°F/29°C
Tuesday
October 03, 2023
8 pm
82°F
28°C

Overcast clouds
Humidity 78%
Sea 85°F/29°C
Tuesday
October 03, 2023
11 pm
81.6°F
28°C

Light rain
Humidity 81%
Sea 85°F/29°C
Wednesday
October 04, 2023
8 am
82.8°F
29°C

Overcast clouds
Humidity 75%
Sea 85°F/29°C
Wednesday
October 04, 2023
11 am
83.7°F
29°C

Overcast clouds
Humidity 77%
Sea 85°F/29°C
Wednesday
October 04, 2023
2 pm
83.7°F
29°C

Light rain
Humidity 78%
Sea 85°F/29°C
Wednesday
October 04, 2023
5 pm
82.7°F
29°C

Overcast clouds
Humidity 77%
Sea 85°F/29°C
Wednesday
October 04, 2023
8 pm
82.2°F
28°C

Overcast clouds
Humidity 77%
Sea 85°F/29°C
Wednesday
October 04, 2023
11 pm
81.7°F
28°C

Overcast clouds
Humidity 78%
Sea 85°F/29°C
Weather uncertainties 2023 to go to Koh Samui ?


When traveling in the tropics as a seaside, rain is not welcome. If you see this indicator, with possible storms, that does not mean that it will rain all day long. When we observe the local rainfall, it is either really zero or very weak. Meteorologists prefer to be pessimistic. So observe below, the skies photographed during a week announced stormy in Asia. It did not rain once. I invite you to integrate this parameter before going to Koh Samui for a good trip to the sun!



