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Weather in Samui

Rainy season in Koh Samui

The rainy season on Koh Samui lasts from April to November. The main rainy season is from May to October. During this period, it can rain heavily on the island with thunderstorms, and can last for several days. However, this does not mean that there is no sun on the island at this time and there can be many sunny days during the rainy season. It is also worth considering that the rains on Koh Samui can be uneven and in some places they can be more or less.

When does the rainy season start in Koh Samui?

The rainy season on Koh Samui starts in October and lasts until December. At this time, the island can get quite a lot of rain. At the same time, if you plan to visit Koh Samui during this period, then the island offers many opportunities for a pleasant pastime, as well as low prices compared to the high season.

High (dry) season in Koh Samui

The best season to visit Koh Samui is between January and August. At this time, the island is dry and warm, ideal conditions for relaxing on the beach and practicing water sports. The average air temperature during this period is about 28 degrees Celsius, and the sea temperature reaches 29 degrees.

When is the best time to go to Koh Samui?

The best time to visit Koh Samui is between January and August. At this time, the high season begins on the island, which promises warm and sunny weather. If you are planning to visit Koh Samui during the rainy season, don't be discouraged, as the island has many places to visit and various activities, including outdoor activities, that you can enjoy in any weather.

At any time of the year, Koh Samui welcomes tourists with its many-sided opportunities for recreation. No matter which season you choose, you are sure to have an unforgettable experience on this beautiful island.

Average monthly temperature,
°C day and night, water
Jan
+28
+27
+28
Feb
+28
+27
+28
Mar
+29
+28
+29
Apr
+31
+29
+30
May
+32
+29
+31
Jun
+31
+29
+30
Jul
+31
+29
+30
Aug
+31
+28
+29
Sep
+30
+28
+29
Oct
+30
+28
+29
Nov
+30
+28
+29
Dec
+29
+27
+28
January
Is one of the coolest months on Koh Samui, but the average air temperature is still quite high. The average temperature during the day is 28.7°C and at night - 27.2°C. During this month the sea temperature is usually around 28.0°C.

The number of rainy days in January on Koh Samui is about 6 days, however, the precipitation is usually not too heavy and long, and the rest of the month the weather is usually clear and sunny.
Daytime weather
+28°
Weather at night
+27°
Water
+28°
February
In February, on Koh Samui, a gradual increase in air temperature begins, and the number of rainy days usually decreases. The average temperature during the day is 28.9°C and at night - 27.4°C. Sea water temperature this month is usually around 28.3°C.

On average, the number of rainy days in February on Koh Samui is about 4. However, despite the fact that the weather is usually clear and sunny, it can rain intermittently during this month, so it is better to have an umbrella or a raincoat with you.
Daytime weather
+28°
Weather at night
+27°
Water
+28°
March

В марте на острове Самуи сохраняется комфортная температура, средняя температура воздуха днем составляет 29.8°C, а ночью — 28.0°C. Температура воды в море стабильно высокая и достигает 29.2°C. Количество дождливых дней в марте такое же как и в феврале, в среднем 4 дня, что делает этот месяц одним из лучших для посещения острова. В это время года на Самуи можно наслаждаться яркими солнечными днями и чистыми пляжами, не беспокоясь о дождях.

Daytime weather
+29°
Weather at night
+28°
Water
+29°
April

In March, a comfortable temperature remains on Koh Samui, the average air temperature during the day is 29.8°C, and at night - 28.0°C. The water temperature in the sea is consistently high and reaches 29.2°C. The number of rainy days in March is the same as in February, averaging 4 days, making this one of the best months to visit the island. At this time of the year, you can enjoy bright sunny days and clean beaches on Koh Samui without worrying about rain.

Daytime weather
+31°
Weather at night
+29°
Water
+30°
May

In May, temperatures remain high on Koh Samui. The average air temperature during the day is 31.6°C, and at night - 29.5°C. The sea temperature continues to rise and reaches 30.8°C. However, the number of rainy days increases to 8 days and there may be short showers.

Daytime weather
+32°
Weather at night
+29°
Water
+31°
June

it is one of the hottest months in the region, with daytime temperatures averaging 31.4°C. The nights are also very warm, with an average temperature of 29.1°C. The sea temperature in June is also very high, at 30.3°C. However, the number of rainy days in this month is quite high and amounts to 8 days.

Daytime weather
+31°
Weather at night
+29°
Water
+30°
July

This month is also very hot, with an average temperature of 31.0°C during the day and 28.6°C at night. The sea water temperature remains high at 29.8°C. The number of rainy days in July is slightly higher than in June and is 9 days. However, the rains mostly come in the form of intermittent downpours.

Daytime weather
+31°
Weather at night
+29°
Water
+30°
August

The last month of the hottest period in the region. The average temperature during the day is 31.0°C and at night - 28.5°C. The sea temperature also remains high at 29.5°C. The number of rainy days in August decreases to 6 days. However, the air this month is still very humid and stuffy.

Daytime weather
+31°
Weather at night
+28°
Water
+29°
September

September is the end of the summer season in this region. The average temperature during the day is 30.3°C and at night - 28.2°C. The sea water temperature remains high and reaches 29.4°C. However, the number of rainy days increases to 9. This time of the year usually sees more windy weather as well as heavy showers.

Daytime weather
+30°
Weather at night
+28°
Water
+29°
October

October is a transitional month when the summer season ends and the cool season begins. The average temperature during the day is 30.1°C and at night - 28.2°C. The sea water temperature drops to 29.3°C. The number of rainy days during this period increases to 12. During this time of year, there is moderate humidity, as well as heavy showers and thunderstorms.

Daytime weather
+30°
Weather at night
+28°
Water
+29°
November
November is the beginning of the rainy season in this area of Thailand. Although the rains can be quite intense, the air temperature is still quite warm and comfortable for relaxing on the beach. The average temperature during the day is around 29.8°C and at night around 28.3°C. The sea temperature remains very pleasant, around 29.1°C.

However, do not forget that in November it can be quite windy on Koh Samui. It can be somewhat inconvenient for relaxing on the beach, but at the same time it allows you to do water sports such as surfing or windsurfing.
Daytime weather
+30°
Weather at night
+28°
Water
+29°
December
December is the middle of the rainy season on Koh Samui. This month, the number of rainy days is reduced, and in general, the weather becomes more comfortable. The average temperature during the day is around 29°C and at night around 27.6°C. The sea water temperature gets a little cooler in December, around 28.3°C.

This month is one of the most popular times to visit Koh Samui. Sunny days and mild winds make the beaches more pleasant and comfortable to relax. You can also enjoy the festive atmosphere that covers the whole country on the eve of Christmas and New Year.
Daytime weather
+29°
Weather at night
+27°
Water
+28°
Best Resorts
Average monthly temperature
+31°C afternoon, +25°C at night, +29°C water
Average monthly temperature
+30°C afternoon, +28°C at night, +29°C water
Average monthly temperature
+32°C afternoon, +21°C at night, +27°C water
Average monthly temperature
+31°C afternoon, +28°C at night, +30°C water
Average monthly temperature
+31°C afternoon, +27°C at night, +29°C water
Average monthly temperature
+31°C afternoon, +26°C at night, +29°C water