Safety
ONWR Issues Heavy Rain and Flash Flood Warning for 18 Provinces
The Office of the National Water Resources (ONWR) has issued a warning for heavy rainfall and potential flash floods across 18 provinces from August 19–21, 2026.
According to a report by Prachachat Business, the Office of the National Water Resources (ONWR) has issued an urgent alert regarding severe weather conditions expected between August 19 and August 21, 2026. The warning follows the movement of a monsoon trough across Northern Thailand and the upper Northeastern region, which is being intensified by a strong southwest monsoon.
Residents and travelers in 18 designated provinces are advised to remain vigilant against the risks of heavy to very heavy rainfall. The ONWR specifically highlights the potential for flash floods, forest runoff, and landslides in vulnerable areas, as well as the possibility of riverbanks overflowing.
For those currently in or planning to visit these regions, it is essential to monitor local weather updates closely and follow instructions from provincial authorities. While the ONWR has identified the high-risk period and the affected regions, the specific intensity of rainfall in localized areas remains subject to change. Travelers should exercise caution when navigating mountainous terrain or areas prone to flooding during this three-day window. Please stay tuned to official government channels for real-time updates on water levels and safety protocols.