Safety
Thailand Issues Heavy Rain and Flash Flood Warning for Northern Regions
The Thai Meteorological Department has issued a severe weather warning for upper Thailand, forecasting heavy rainfall and potential flash floods through August 21, 2026.
On August 20, 2026, the Thai Meteorological Department (TMD) released announcement No. 12, warning of heavy to very heavy rainfall across upper Thailand. This weather pattern, effective through August 21, 2026, is attributed to a monsoon trough passing through the northern and northeastern regions, connecting to a low-pressure cell near Hainan Island, China. Additionally, a relatively strong southwest monsoon is currently affecting the Andaman Sea and the Gulf of Thailand.
For residents and travelers, the TMD has identified 38 provinces at risk of significant rainfall. The primary concerns include flash floods and forest runoff, particularly in low-lying areas and regions near mountain slopes or natural waterways. Authorities advise the public to exercise caution, avoid travel through areas prone to recurring flooding, and remain vigilant regarding potential water accumulation.
Furthermore, maritime conditions are expected to be rough. The upper Andaman Sea and the upper Gulf of Thailand are experiencing relatively strong winds, with wave heights reaching 2 to 3 meters. In areas affected by thunderstorms, wave heights may exceed this range. While the TMD has provided specific warnings for these regions, travelers should continue to monitor local weather updates and follow guidance from provincial authorities, as the exact impact on specific transport routes remains subject to changing conditions.