Weather Update: Meteorological Department Issues Heavy Rain Warning for 40 Provinces
Thailand's Meteorological Department warns of heavy rain and thunderstorms across 40 provinces starting May 27, with the western south and eastern regions facing the most severe conditions through June 1 as monsoon winds intensify.
On May 27, 2025, the Thai Meteorological Department forecasted thunderstorms and heavy rain in some areas of the western south region over the next 24 hours, driven by moderate southwest monsoon winds covering the Andaman Sea, Thailand, and the Gulf of Thailand. The public is urged to exercise caution against dangers from heavy rainfall and accumulated water. Waves in the Andaman Sea and Gulf of Thailand are expected to be moderate, with the upper Andaman Sea experiencing waves around 2 meters high, while the lower Andaman Sea and upper Gulf of Thailand will see 1-2 meter waves. Areas with thunderstorms may experience waves exceeding 2 meters, and fishermen are advised to navigate carefully and avoid thunderstorm zones. From May 28 to June 1, rainfall is expected to increase with heavy precipitation likely in some areas of the eastern region and western south, as a monsoon trough passes over northern Thailand combined with strengthening southwest monsoon winds. Upper Andaman Sea waves are forecast to reach 2-3 meters, with thunderstorm areas potentially exceeding 3 meters. Regional forecasts include: Northern region 40% thunderstorm coverage mainly in Mae Hong Son, Chiang Mai, Lampoon, Phayao, Nan, Uttaradit, Tak, Kamphaeng Phet, Phichit, Phitsanulok, and Phetchabun with lows of 22-26°C and highs of 34-37°C. Northeastern region 30% thunderstorms primarily in Loei, Nong Khai, Bueng Kan, Chaiyaphum, Khon Kaen, Kalasin, Maha Sarakham, Roi Et, and Nakhon Ratchasima with lows of 24-26°C and highs of 35-38°C. Central region 40% thunderstorms mainly in Nakhon Sawan, Uthai Thani, Lopburi, Saraburi, Kanchanaburi, Ratchaburi, Nakhon Pathom, and Samut Songkhram with lows of 25-27°C and highs of 36-38°C. Eastern region 40% thunderstorms in Nakhon Nayok, Prachuap Khiri Khan, Rayong, Chanthaburi, and Trat with lows of 24-27°C and highs of 33-38°C, seas with 1-2 meter waves increasing to over 2 meters in thunderstorm areas. Southern east coast 40% thunderstorms in Chumphon, Surat Thani, and Nakhon Si Thammarat with lows of 23-26°C and highs of 34-36°C, seas around 1 meter near shore and 1-2 meters offshore, exceeding 2 meters in thunderstorm zones. Southern west coast 70% thunderstorms with heavy rain in some areas of Ranong, Phang Nga, and Phuket with lows of 23-26°C and highs of 31-34°C.
