Heavy rain and thunderstorms will affect 56 Thai provinces over the next 24 hours, with the Northeast and Andaman coast facing the heaviest downpours and risk of flash floods and landslides. Authorities warn residents in low-lying and hills
May 20, 2025 — The Thai Meteorological Department forecasts continuous rainfall across Thailand over the next 24 hours, with heavy to very heavy rain in parts of the western Andaman coast, Northeast, and Eastern regions. Heavy rainfall is also expected in the North, Central Thailand, and Bangkok with surrounding areas. The weather is driven by a strong southwest monsoon covering the northern Andaman Sea and Thailand, combined with a low-pressure system over northern Vietnam. Authorities warn residents of dangers from intense rainfall and accumulated water that could trigger flash floods and landslides, particularly in hillside areas, near waterways, and low-lying zones. The public is also advised to maintain health during this weather transition.
Sea conditions in the northern Andaman are moderately rough with waves 2-3 meters high, exceeding 3 meters during thunderstorms. The lower Andaman and northern Gulf of Thailand have approximately 2-meter waves, exceeding 2 meters during storms. Fishermen are urged to exercise caution and avoid thunderstorm areas. Small boats in the northern Andaman should remain ashore.
Regional Forecast (06:00 today to 06:00 tomorrow):
North: 60% thunderstorms with heavy rain in some areas, particularly in Nan, Tak, Sukhothai, Uttaradit, Kamphaeng Phet, Phichit, Phitsanulok, and Phetchabun provinces. Temperatures: 24-26°C low, 33-38°C high. Southwest winds 10-20 km/h.
Northeast: 70% thunderstorms with heavy to very heavy rain in some areas, particularly in Loei, Nong Khai, Bueng Kan, Nong Bua Lamphu, Udon Thani, Sakon Nakhon, Nakhon Phanom, Chaiyaphum, Khon Kaen, Kalasin, Maha Sarakham, Mukdahan, Roi Et, Yasothon, Amnat Charoen, Nakhon Ratchasima, Sisaket, and Ubon Ratchathani. Temperatures: 23-25°C low, 30-34°C high. Southwest winds 10-20 km/h.
Central: 60% thunderstorms with heavy rain in some areas, particularly in Nakhon Sawan, Uthai Thani, Chainat, Lopburi, Saraburi, Singburi, Ang Thong, Ayutthaya, Suphan Buri, Nakhon Pathom, Kanchanaburi, and Ratchaburi. Temperatures: 24-26°C low, 31-35°C high. Southwest winds 10-20 km/h.
East: 60% thunderstorms with heavy to very heavy rain in some areas, particularly in Nakhon Nayok, Prachuap Khiri Khan, Chachoengsao, Chonburi, Rayong, Chanthaburi, and Trat. Temperatures: 25-28°C low, 31-34°C high. Southwest winds 20-35 km/h. Sea waves approximately 2 meters, exceeding 2 meters during thunderstorms.
South (Eastern Coast): 60% thunderstorms with heavy rain in some areas, particularly in Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, and Songkhla. Temperatures: 23-26°C low, 30-35°C high. From Surat Thani northward: Southwest winds 20-35 km/h, sea waves approximately 2 meters offshore and during thunderstorms exceeding 2 meters. From Nakhon Si Thammarat southward: Southwest winds 15-35 km/h, sea waves 1-2 meters near shore, approximately 2 meters offshore during rain.