September weather forecast
Thailand

As Thailand enters September, the monsoon season shows initial signs of tapering off, especially towards the month's end. While rain remains frequent, the intensity and duration of downpours start to lessen in several regions, hinting at the upcoming transition to drier months.

In Northern Thailand, adjoining Myanmar and Laos, the rain persists but becomes somewhat sporadic. Prolonged showers are less common, and periods of sunshine begin to punctuate the cloudy days. The temperature spectrum remains comfortable, spanning from 25°C (77°F) to 30°C (86°F), with the decreased rain not yet allowing significant climbs in the thermometer readings.

Bangkok, along with its neighboring territories, witnesses a reduction in rain frequency as September progresses. However, the city still sees regular showers, particularly during the afternoon and evening. Temperature variations in the capital city hover between 27°C (80.6°F) to 31°C (87.8°F). The blend of urban infrastructure and lingering humidity can occasionally create a slightly muggy atmosphere during the non-rainy intervals.

The western coast, including destinations like Phuket and Krabi, continues to experience regular rainfall in September, albeit with less vigor than the preceding months. With the southwest monsoon gradually receding, the instances of storms and rough seas diminish. Travelers, however, should remain alert to sudden changes in weather, as September can still usher in unexpected downpours.

Contrasting with August, September offers a breather as the monsoon slowly loses its grip on Thailand. Rainfall, although frequent, becomes more manageable, and prolonged sunny spells start to reappear, particularly in the latter half of the month. This transition paints a picture of what to expect as Thailand approaches October, a month typically characterized by further reductions in rain and the onset of cooler, pleasant days.

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• Bangkok - September »
  With an average relative humidity of 79%, September is the most humid month in Bangkok, Thailand. The months with the least sunshine in Bangkok are August and September, with an average of 5.2h of sunshine.
• Chiang Mai - September »
  The months with the highest humidity in Chiang Mai are August and September, with an average relative humidity of 81%. August and September, with an average relative humidity of 81%, are the most humid months in Chiang Mai.
• Pattaya - September »
  In Pattaya, Thailand, the average seawater temperature in September is 29.1°C (84.4°F). In Pattaya the average seawater temperature in September is 29.1°C (84.4°F).
• Phuket - September »
  The months with the highest humidity in Phuket are September and October, with an average relative humidity of 82%. The months with the highest humidity in Phuket are September and October, with an average relative humidity of 82%.
• Nakhon Ratchasima - September »
  The month with the most rainfall in Nakhon Ratchasima is September, when the rain falls for 19 days and typically aggregates up to 228mm (8.98") of precipitation. September is the most humid month in Nakhon Ratchasima, with an average relative humidity of 80%.
• Udon Thani - September »
  The months with the highest humidity in Udon Thani are August and September, with an average relative humidity of 81%. The months with the highest humidity in Udon Thani, Thailand, are August and September, with an average relative humidity of 81%.
• Hua Hin - September »
  The average heat index, which combines air temperature and relative humidity, in September is calculated to be 45°C (113°F). In Hua Hin in September, the average water temperature is 29°C (84.2°F).
• Krabi - September »
  The month with the most rainfall in Krabi is September, when the rain falls for 22 days and typically aggregates up to 355mm (13.98") of precipitation. The month with the most rainfall in Krabi is September, when the rain falls for 22 days and typically aggregates up to 355mm (13.98") of precipitation.
• Hat Yai - September »
  In September, the average heat index, which calculates the temperature value influenced by the moisture in the air, is computed to be 47°C (116.6°F). In September, Hat Yai experiences a minor retreat in temperatures, providing some relief to the scorching summer heat.
• Surat Thani - September »
  September brings the highest rainfall of the year to Surat Thani, with average precipitation of 188mm (7.4") over 19 days. In Surat Thani in September, during 19 rainfall days, 188mm (7.4") of precipitation is typically accumulated.
• Chiang Rai - September »
  In Chiang Rai during September, the rain falls for 18 days and regularly aggregates up to 284mm (11.18") of precipitation. In Chiang Rai, Thailand, the average relative humidity in September is 83%.
• Khon Kaen - September »
  The month with the most rainfall in Khon Kaen is September, when the rain falls for 18 days and typically aggregates up to 232mm (9.13") of precipitation. The most humid month in Khon Kaen is September, with an average relative humidity of 83%.