"Meteorological Department" (Thai Meteorological Department) Issues the 6th announcement warning "Heavy to very heavy rainfall" From 17 to 20 September 2026, may cause flash floods and sudden runoff
17 September 2026The Meteorological Departmentannounced "Heavy to very heavy rainfall over Thailand and strong winds in the Andaman Sea" (effective from 17 to 20 September 2026) In its 6th announcement, it stated that from 17 to 20 September 2026, Thailand will experience heavy to very heavy rain in some areas, beginning with impacts in the northern and northeastern regions on 17 September 2026. Subsequently, the central, eastern, and southern regions will be affected the following day (18 September 2026).
This is because a high-pressure system or cold air mass from China will extend over the upper northern and northeastern regions, causing the monsoon trough to shift across the lower central, eastern, and upper southern regions. Additionally, the southwest monsoon blowing over the Andaman Sea, Thailand, and the Gulf of Thailand will strengthen.
Residents across Thailand are advised to beware of dangers from heavy to very heavy rainfall and accumulated rain, which may lead to flash floods and sudden runoff, especially in foothill areas near waterways and low-lying zones. Avoid traveling through frequently flooded routes, particularly in low-lying areas prone to short-term flooding.
Meanwhile, waves in the Andaman Sea are relatively strong, reaching 2-3 meters high, and exceeding 3 meters in areas with thunderstorms. Mariners in the Gulf of Thailand and Andaman Sea should navigate with caution and avoid sailing in stormy conditions. Small boats in the Andaman Sea are advised to stay ashore from 17 to 20 September 2026.
For safety and to minimize potential impacts, people are urged to plan their activities and travel carefully during this period. They should follow updates from the Meteorological Department via its website http://www.tmd.go.th or by calling 0-2399-4012-13 and 1182, available 24 hours.