Meteorology Department Issues Alert for Heavy Rainfall and Strong Winds
Thailand's Meteorology Department warns of heavy rainfall and strong waves across 59 provinces from September 17-20, with flash flooding and mudslides likely in hilly and low-lying areas. Small boats should remain ashore in the Andaman Sea
On September 17, 2025, the Thai Meteorology Department issued alert number 5 (209/2569) warning of heavy to very heavy rainfall across Thailand and strong waves in the Andaman Sea from September 17-20, 2025. Heavy rainfall is expected to begin in the northern and northeastern regions on September 17, with impacts spreading to the central, eastern, and southern regions on September 18. The warning is driven by a cold air mass moving down from China combined with monsoon systems affecting the region, which will intensify the southwestern monsoon winds over the Andaman Sea, Thailand, and the Gulf of Thailand. The Meteorology Department has identified 59 provinces expecting heavy rain.
The public is urged to exercise caution against heavy rainfall and accumulated water that may cause flash flooding and mudslides, particularly in hilly areas near waterways and low-lying zones. Travel through areas prone to repeated flooding should be avoided, especially in low-lying areas. Waves in the Andaman Sea are expected to be moderately strong at 2-3 meters high, rising above 3 meters in areas with thunderstorms.
Fishermen in the Gulf of Thailand and Andaman Sea should navigate with extreme caution and avoid thunderstorm areas. Small boats in the Andaman Sea should remain ashore from September 17-20, 2025. The public is advised to plan daily activities and travel carefully during this period and monitor updates from the Meteorology Department at www.tmd.go.th, by calling 0-2399-4012-13, or 1182, available 24 hours. The next update will be issued on September 17 at 5:00 p.m.
