Thailand Issues Warning for Heavy Rainfall and Rough Seas

The Thai Meteorological Department (TMD) has released its 10th weather advisory (214/2569), warning of heavy to very heavy rainfall across Thailand through September 20, 2026. The weather pattern is driven by a cold air mass from China meeting a monsoon trough, compounded by strong southwesterly winds over the Andaman Sea and the Gulf of Thailand.

Residents and travelers are advised to exercise caution, particularly in low-lying areas and regions near hillsides, where there is an elevated risk of flash floods and forest runoff. The TMD specifically recommends avoiding travel on routes prone to recurring flooding.

Maritime conditions are also affected, with the upper Andaman Sea experiencing waves between 2 and 3 meters, and exceeding 3 meters in areas with thunderstorms. Mariners in the Gulf of Thailand and the Andaman Sea are urged to navigate with extreme caution and avoid storm-affected zones. Small vessels in the upper Andaman Sea are advised to remain ashore through September 20.

While the advisory provides a clear outlook for the immediate period, residents should monitor local news for updates on specific provincial impacts, as the intensity of rainfall can vary significantly by location. Travelers are encouraged to check their transit routes and local weather forecasts before embarking on journeys in affected regions.