Thailand weather warning issued for heavy rain and flash floods

The Thai Meteorological Department has issued warnings for heavy to very heavy rainfall across much of Thailand, effective through September 7. The weather is being driven by a monsoon trough passing through the North and upper Northeast, combined with a moderate southwest monsoon affecting the Andaman Sea and the Gulf of Thailand.

Significant risks include flash floods, forest runoff, and landslides, particularly in low-lying areas and near mountain slopes. The Mekong River basin is specifically noted as a high-risk zone. In the North, provinces such as Chiang Rai, Nan, and Phayao are expected to face severe impacts. In the Northeast, heavy rain is forecast for several provinces, with very heavy falls expected in Loei, Nakhon Phanom, and Ubon Ratchathani.

Maritime conditions are also unstable, with waves in the upper Andaman Sea reaching approximately two metres, potentially exceeding that height during thunderstorms. Residents and travelers are advised to exercise caution and avoid flood-prone routes.