Heavy rainfall warning: 33 provinces hit, 70% of South Thailand to be impacted

Heavy rainfall is expected in 33 provinces across Thailand, with the southern region facing a high risk of flash floods and landslides. The Thai Meteorological Department urges citizens to remain vigilant to sudden flooding from June 2 as 70% of the area is expected to experience torrential downpours.

The department has issued a 24-hour weather forecast warning of thunderstorms and heavy rainfall in certain areas of the eastern and southern provinces. Residents in these regions are advised to stay alert to potential flash floods and forest runoff, especially in areas on hill slopes, near watercourses, and low-lying zones. This significant weather event is due to the prevailing strong southwest monsoon that continues to blow across the Andaman Sea, southern Thailand, and the Gulf of Thailand.

The department also advises caution for sailors in the Andaman Sea and the Gulf of Thailand due to rough seas. Waves are expected to be around 2 to 3 metres high in the Andaman Sea and even higher during thunderstorms. In the Gulf of Thailand, waves are predicted to be 1 to 2 metres high, increasing during storm activity. It is recommended that small boats in the Andaman Sea avoid making trips until June 6.

According to the weather forecast, the northern regions are expected to experience 20% thunderstorm coverage, with strong winds in some areas. Provinces such as Mae Hong Son, Chiang Mai, Chiang Rai, Nan, Tak, Kamphaengphet, and Phetchabun will experience temperatures ranging from 24 to 28°C at the lowest, and 37 to 40°C at the highest, with southwest winds blowing at speeds of 10 to 20 kilometres per hour.

The northeastern regions are also anticipating 20% thunderstorm coverage with strong winds in parts of the region. Provinces, including Nong Khai, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Chaiyaphum, Nakhon Ratchasima, Buri Ram, Surin, Sisaket, and Ubon Ratchathani, will experience low temperatures of 24 to 28°C and high temperatures of 36 to 39°C, with southwest winds blowing at speeds of 10 to 20 kilometres per hour.

The central regions will face a lower 10% thunderstorm coverage, mainly in the provinces of Uthai Thani, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon, and Samut Songkhram. Temperatures are expected to range from 24 to 27°C at the lowest, and 36 to 39°C at the highest, with southwest winds blowing at speeds of 10 to 20 kilometres per hour.

In the east, provinces like Chanthaburi and Trat will experience a 20% thunderstorm coverage and heavy rainfall in some areas. The temperatures are expected to range from 25 to 29°C at the lowest, and 32 to 37°C at the highest, with southwest winds blowing at speeds of 20 to 35 kilometre per hour. The sea will have waves about 2 metres high, increasing to over 2 metres during thunderstorms.

The southern-east coast, including Prachuap Khiri Khan, Chumphon, Surat Thani, and Nakhon Si Thammarat, will face 40% thunderstorm coverage. Temperatures will vary between 24 to 28°C at the lowest and 32 to 38°C at the highest, with southwest winds blowing at speeds of 15 to 35 kilometre per hour. Waves in the sea will be around 1 to 2 metres high, increasing to over 2 metres during storm activity.

The southern-west coast, with provinces like Ranong, Phang Nga, and Phuket, will face 70% thunderstorm coverage, and heavy rainfall in some areas. The temperatures are expected to range from 23 to 26°C at the lowest, and 30 to 33°C at the highest, with southwest winds blowing at speeds of 20 to 40 kilometres per hour. The sea will have waves 2 to 3 metres high, surging to over 3 metres during thunderstorms.

Bangkok and its vicinities are predicted to experience 10% thunderstorm coverage, mostly in the afternoon and evening. The temperatures will range from 26 to 29°C at the lowest, and 33 to 38°C at the highest, with southwest winds blowing at speeds of 10 to 20 kilometres per hour.