Moderate southwest monsoon brings thundershowers and rough seas across Thailand

Residents of the South are urged to be cautious of heavy rainfall, which could lead to localized flooding.

The moderate southwest monsoon is prevailing over the Andaman Sea, Southern Thailand, and the Gulf of Thailand, while a weak monsoon trough extends across Myanmar, the upper Laos, and into a low-pressure system over upper Vietnam. 

This weather pattern is expected to bring thundershowers and isolated heavy rain to the upper Northeast and the South, the Thai Meteorological Department forecast on Thursday.

Residents of the South are urged to be cautious of heavy rainfall, which could lead to localized flooding, the department said.

In the Andaman Sea, moderate winds are causing waves to reach 2 metres high, with waves exceeding 2 metres during thundershowers. All ships in the Andaman Sea and Gulf of Thailand are advised to proceed with caution and avoid areas affected by thundershowers, the department warned.

The weather forecast for the next 24 hours is as follows:

North: Scattered thundershowers mostly in Mae Hong Son, Chiang Rai, Phayao, Nan, Uttaradit and Tak; minimum temperature 23-26 degrees Celsius, maximum 33-37°C. 

Northeast: Scattered thundershowers and isolated heavy rain in Loei, Nong Khai, Bueng Kan, Udon Thani, Sakon Nakhon, Nakhon Phanom and Mukdahan; minimum 23-26°C, maximum 33-35°C.

Central: Scattered thundershowers mostly in Lopburi, Saraburi, Kanchanaburi and Ratchaburi; minimum 24-26°C, maximum 36-38°C. 



East: Scattered thundershowers and isolated heavy rain in Nakhon Nayok, Prachin Buri, Chonburi, Rayong, Chanthaburi and Trat; minimum 25-27°C, maximum 30-35°C; waves about a metre high and above 2 metres high in thundershowers.

South (east coast): Scattered thundershowers mostly in Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Yala and Narathiwat; minimum 22-26°C, maximum 33-36°C; waves about a metre high and above 2 metres high in thundershowers.

South (west coast): Fairly widespread thundershowers and isolated heavy rain in Ranong, Phang Nga, Phuket, Krabi, Trang and Satun; minimum 25-27°C, maximum 31-34°C; waves about 1-2 metres high and above 2 metres high in thundershowers.

Bangkok metropolitan area: Scattered thundershowers; minimum 27-28°C, maximum 34-37°C.

(2025/06/05-00:00)