Safety
Severe Weather Alert: Heavy Rainfall and Flood Risks Across 47 Provinces
The Thai Meteorological Department has issued a severe weather warning for 47 provinces, forecasting heavy rain, flash floods, and high waves for September 20, 2026.
On September 19, 2026, the Thai Meteorological Department (TMD) issued a critical weather advisory for September 20, 2026, warning that 47 provinces across Thailand face a high risk of heavy rainfall, covering approximately 80% of these areas. The forecast includes Bangkok and its surrounding metropolitan regions.
According to the TMD, the combination of a high-pressure system from China and a monsoon trough passing through the central, eastern, and upper southern regions is driving this instability. Residents and travelers are urged to exercise extreme caution regarding potential flash floods, forest runoff, and landslides, particularly in low-lying areas and regions near mountain slopes. Authorities advise avoiding travel on routes prone to recurring flooding.
Marine conditions are also hazardous. The upper Andaman Sea is experiencing strong winds with waves reaching 2 to 3 meters, potentially exceeding 3 meters during thunderstorms. The lower Andaman Sea and the upper Gulf of Thailand face waves of approximately 2 meters. Small boats in the upper Andaman Sea are advised to remain ashore for at least another 24 hours. Mariners in all affected areas are cautioned to navigate with extreme care and avoid sailing through thunderstorm zones. Travelers should monitor local news for updates as weather conditions evolve.