Bangkok
Thailand
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Bangkok, Thailand

A beautiful park in spring outside the Wat Ratchanatdaram Temple in the heart of Bangkok, Thailand
A beautiful park in spring outside the Wat Ratchanatdaram Temple in the heart of Bangkok, Thailand
The first month of the autumn, September, is also a hot month in Bangkok, Thailand, with average temperature varying between 25°C (77°F) and 32.8°C (91°F).

Temperature

In September, the average high-temperature is relatively the same as in August - a still tropical 32.8°C (91°F). In September, the average low-temperature is 25°C (77°F).

Heat index

The average heat index in September is appraised at a blazing hot 46.9°C (116.4°F). Be wary - heat exhaustion and heat cramps are highly anticipated. With continued activity, heatstroke is very likely.
Note that heat index values are valued for light wind and location in the shade. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature', 'apparent temperature', 'feels like', or 'real feel', is a measure that combines both air temperature and relative humidity into a single value that indicates how hot the weather feels. Additional factors like differences in body mass, height, and shape, wind, metabolic differences, and activity influence one's weather impression. Be aware that direct exposure to sunlight increases heat impact, and may raise the heat index additionally, by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it is vital to remain hydrated, particularly during prolonged physical activities.
The human body cools itself through perspiration, as excessive warmth is removed from the body through sweat evaporation. With a lot of moisture in the air, the evaporation process is not as effective, and the body does not cool down as efficiently, creating a perception of overheating. When heat gain exceeds the level the body can remove, body temperature begins to rise, and heat-related illnesses and disorders may develop.

Humidity

September is the most humid month, with an average relative humidity of 79%.

Rainfall

September is the month with the most rainfall. Rain falls for 21 days and accumulates 334.3mm (13.16") of precipitation.

Sea temperature

In Bangkok, in September, the average water temperature is 28.8°C (83.8°F).
Note: For swimming, diving, and other water activities, temperatures between 25°C (77°F) and 29°C (84.2°F) are perceived as very enjoyable and pleasurable for prolonged periods without feeling uncomfortable.

Daylight

In Bangkok, Thailand, the average length of the day is 12.2h.

Sunshine

Months with the least sunshine are August and September, with an average of 5.2h of sunshine.

UV index

February through September, with an average maximum UV index of 12, are months with the highest UV index. A UV Index estimate of 11, and higher, represents an extreme threat to health from the exposure to the Sun's UV rays for the ordinary person.
Note: The average daily UV index of 12 transform into the following instructions:
Practice all essential precautions. Protection against sun damage is crucial. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. A broad-spectrum sunscreen of SPF 30+ should be liberally applied and re-applied every two hours, and immediately after an outdoor workout or a swim. Beware! The strength of the UV rays is significantly increased by the reflection of the water and sand.

What is the temperature in September in Bangkok?

In September, the average high-temperature is 32.8°C (91°F), and the average low-temperature is 25°C (77°F). In September, the average heat index (a.k.a. 'real feel', 'felt air temperature'), that combines relative humidity and air temperature, is calculated to 46.9°C (116.4°F).

What is the most humid month in Bangkok?

With an average relative humidity of 79%, September is the most humid month.

What is the average humidity in September in Bangkok?

In Bangkok, the average relative humidity in September is 79%.

How much does it rain in Bangkok in September?

In Bangkok, Thailand, in September, during 21 rainfall days, 334.3mm (13.16") of precipitation is typically accumulated.

What is the wettest month in Bangkok?

The month with the most rainfall in Bangkok, Thailand, is September when the rain falls for 21 days and typically aggregates up to 334.3mm (13.16") of precipitation.

What is the water temperature in September in Bangkok?

In September, the average sea temperature is 28.8°C (83.8°F). Water temperature between 25°C (77°F) and 29°C (84.2°F) is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.

What is the average length of the day in September in Bangkok?

The average length of the day in September is 12.2h.

What is the month with the least sunshine in Bangkok?

Months with the least sunshine in Bangkok are August and September, with an average of 5.2h of sunshine.

How many hours of sunshine does Bangkok have in September?

The average sunshine in September in Bangkok is 5.2h.

What are the months with the highest UV index in Bangkok?

Months with the highest UV index are February through September, with an average maximum UV index of 12.

What is the UV index reading in September in Bangkok?

In September, the average daily maximum UV index in Bangkok is 12. A UV Index reading of 11, and higher, represents an extreme health vulnerability from unprotected exposure to the UV radiation.
Average temperature in September - Bangkok, Thailand
  • Average high temperature in September: 32.8°C

The warmest month (with the highest average high temperature) is April (35.4°C).
The month with the lowest average high temperature is December (31.7°C).

  • Average low temperature in September: 25°C

The month with the highest average low temperature is April (26.9°C).
The coldest month (with the lowest average low temperature) is December (22°C).

Average humidity in September - Bangkok, Thailand
  • Average humidity in September: 79%

The month with the highest relative humidity is September (79%).
The month with the lowest relative humidity is December (66%).

Average rainfall in September - Bangkok, Thailand
  • Average rainfall in September: 334.3mm

The wettest month (with the highest rainfall) is September (334.3mm).
The driest month (with the lowest rainfall) is December (6.3mm).

Average rainfall days in September - Bangkok, Thailand
  • Average rainfall days in September: 21 days

The month with the highest number of rainy days is September (21 days).
Months with the lowest number of rainy days are January and December (1 days).

Average sea temperature in September - Bangkok, Thailand
  • Average sea temperature in September: 28.8°C

The best month for swimming (with the highest average sea temperature) is May (29.9°C).
The coldest month (with the lowest average sea temperature) is January (26.7°C).

Average daylight in September / Average sunshine in September - Bangkok, Thailand
  • Average daylight in September: 12.2h

The month with the longest days is June (Average daylight: 12.9h).
The month with shortest days is December (Average daylight: 11.3h).

  • Average sunshine in September: 5.2h

The month with most sunshine is February (Average sunshine: 9h).
Months with least sunshine are August and September (Average sunshine: 5.2).

Average UV index in September - Bangkok, Thailand
  • Average UV index in September: 12

Months with the highest UV index are February, March, April, May, June, July, August and September (UV index 12).
The month with the lowest UV index is December (UV index 9).