Safety
Thailand Issues Alert for Heavy Rain and Flash Floods Across 39 Provinces
The Department of Disaster Prevention and Mitigation has warned of severe weather conditions, including flash floods and landslides, affecting 39 provinces from August 18–21, 2026.
On August 17, 2026, the Department of Disaster Prevention and Mitigation (DDPM) issued a nationwide alert for 39 provinces, warning of potential flash floods, forest runoff, and landslides. According to Director-General Teerapat Kachamat, the warning follows a forecast from the Thai Meteorological Department regarding heavy to very heavy rainfall expected between August 18 and 21, 2026.
The severe weather is attributed to a monsoon trough passing through the upper North and Northeast regions, combined with a strengthening southwest monsoon over the Andaman Sea and the Gulf of Thailand. Residents and travelers in these regions are advised to monitor local weather updates closely, as the conditions may lead to hazardous travel and localized flooding.
Additionally, the DDPM highlighted specific concerns for three southern provinces, where coastal areas are expected to face strong winds and rough seas. From August 19 to 21, the upper Andaman Sea is projected to experience waves between 2 and 3 meters high, with waves exceeding 3 meters in areas affected by thunderstorms. While the DDPM has identified the affected provinces, specific evacuation orders or localized road closures remain subject to ongoing monitoring by local authorities. Travelers are encouraged to check official government channels before planning trips to mountainous or coastal areas during this period.