Persistent rain puts southern Thailand on alert for flash floods
Rain will persist in the South as Bangkok and other regions see increased rainfall and gusty winds. Waves will exceed 3 metres in thunderstorms.
- Thailand's meteorological department has issued a heavy to very heavy rain warning for the southern region, effective from Wednesday until Sunday.
- The persistent rainfall creates a significant risk of flash floods and sudden runoff, especially in foothill and low-lying areas.
- The severe weather is caused by a monsoon trough and a southwest monsoon affecting the region.
- Mariners are also being warned, as waves in the Andaman Sea and Gulf of Thailand are forecast to exceed 3 meters in areas with thunderstorms.
The Thai Meteorological Department issued a heavy to very heavy rain warning for Thailand at 5pm on Wednesday (October 21, 2026), with the alert remaining in effect until Sunday.
During this period, the South will experience persistent rain, with heavy to very heavy downpours in some areas.
Rainfall will also increase in the lower Northeast, the lower Central region, including Bangkok and surrounding areas, the East and the upper South, with strong gusts in some places.
People in the affected areas have been advised to watch for strong gusts, heavy to very heavy rain and the effects of continued rainfall accumulation, which could trigger flash floods and sudden runoff in foothill and low-lying areas.
The conditions are being driven by a monsoon trough across the central part of the South and a southwest monsoon over the lower Andaman Sea.
Meanwhile, a high-pressure system, or cold air mass, from China will extend over the upper North, the upper Northeast and the South China Sea, bringing easterly winds over Thailand and the Gulf of Thailand.
Waves in the Andaman Sea and the Gulf of Thailand are forecast to exceed 3 metres in areas affected by thunderstorms.
Mariners in both areas have been advised to proceed with caution and avoid sailing through thunderstorms.
To stay safe and reduce potential impacts, people have been advised to plan their daily activities and journeys carefully during this period and continue monitoring the department’s announcements.
Updates are available at www.tmd.go.th or by calling 0-2399-4012-13 or 1182, 24 hours a day.
