Thailand's Meteorological Department has issued warnings for 46 provinces expecting heavy rainfall, strong winds, and potential flash flooding over the next 24 hours, with conditions expected to worsen between May 14-18. Residents, farmers, and fishermen are advised to take precautionary measures, particularly in hilly and low-lying areas prone to flooding. Wave heights in coastal areas will also strengthen, with warnings for maritime traffic.
On May 13, 2026, the Thai Meteorological Department forecasts heavy to very heavy rainfall in the southern region over the next 24 hours due to easterly winds covering the Gulf of Thailand and the South. Wave heights are expected to reach approximately 1 meter in the Gulf of Thailand and Andaman Sea, with waves exceeding 2 meters in thunderstorm areas. Fishermen are urged to exercise caution and avoid sailing in stormy conditions.
Northern Thailand will experience thunderstorms with strong gusty winds and heavy rainfall in some areas, caused by southerly and southeasterly winds. While some areas remain hot, the public is advised to be alert to dangers from thunderstorms, strong winds, heavy and accumulated rainfall that may cause flash floods and flash flooding, especially in foothill areas and low-lying regions.
Farmers should reinforce fruit trees and prepare to protect crops and livestock from potential damage, while also maintaining health during changing weather conditions.
From May 14-18, 2026, rainfall will increase across northern, central, eastern, and southern Thailand with heavy rainfall expected in some areas, as a low-pressure system from the lower Bay of Bengal moves northward, combined with strengthening southwest monsoon winds over the Andaman Sea.
Wave conditions in the Andaman Sea and Gulf of Thailand will strengthen, with Andaman Sea waves at 2-3 meters and exceeding 3 meters in thunderstorm areas. The upper Gulf of Thailand will see waves around 2 meters, exceeding 2 meters in thunderstorm zones.
Dust and haze levels remain low in northern Thailand due to rainfall across many areas.
Regional forecasts include:
- North: Hot with 60% thunderstorms, strong winds, and heavy rain in Mae Hong Son, Chiang Mai, Chiang Rai, Lampang, Phayao, Nan, Uttaradit, Tak, Phitsanulok, and Phetchabun. Temperature 21-37°C, southwesterly winds 10-15 km/h.
- Northeast: Hot with 30% thunderstorms and occasional strong winds in Loei, Nong Khai, Nong Bua Lamphu, Udon Thani, Chaiyaphum, Nakhon Ratchasima, Buriram, Surin, Si Sa Ket, and Ubon Ratchathani. Temperature 24-37°C, southerly winds 10-20 km/h.
- Central: Hot with 60% thunderstorms, strong winds, and heavy rain in Uthai Thani, Saraburi, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon, and Samut Songkhram. Temperature 24-37°C, southerly winds 10-20 km/h.
- Eastern: Hot with 60% thunderstorms, strong winds, and heavy rain in Chachoengsao, Rayong, Chanthaburi, and Trat. Temperature 24-37°C, southeasterly winds 15-30 km/h.