TMD issues four-day heavy rain alert for East and South from October 22
Thailand’s weather agency warns of flash floods near foothills and in low-lying areas, with waves above three metres in thunderstorms at sea.
- The Thai Meteorological Department (TMD) has issued a heavy rain warning for eastern and southern Thailand from October 22 to 25.
- The persistent rainfall brings a risk of flash floods and forest run-off in foothills and low-lying areas, along with strong wind gusts.
- Thunderstorms and strong gusts are also forecast for the lower North, lower Northeast, and Central regions, including Bangkok, during the same period.
- Mariners are warned of potentially hazardous conditions, with waves in the Andaman Sea and Gulf of Thailand expected to exceed three meters during thunderstorms.
The Thai Meteorological Department (TMD) issued a four-day heavy rain warning for eastern and southern Thailand at 5am Thailand time on Thursday (October 22, 2026). Persistent rain, with heavy to very heavy downpours in some areas, is forecast through October 25.
Foothills and low-lying areas face flash flood risk
The TMD warned that heavy to very heavy rain and the continuing accumulation of rainfall could trigger flash floods and forest run-off near foothills and in low-lying areas. Residents were also advised to beware of strong wind gusts.
Thunderstorms and isolated strong gusts are forecast for the lower North, lower Northeast and Central region, including Bangkok and surrounding provinces, during October 22–25, according to the TMD.
The TMD advised the public to plan daily activities and journeys carefully during the warning period to reduce potential risks and to monitor subsequent announcements.
Monsoon trough and easterly winds bring unsettled weather
The TMD attributed the wet weather to a monsoon trough crossing the central part of southern Thailand, together with the southwest monsoon prevailing over the lower Andaman Sea.
A high-pressure system, or cold air mass, from China is expected to extend over the upper North, upper Northeast and South China Sea, bringing easterly winds over Thailand and the Gulf of Thailand.
Andaman and Gulf waves could exceed three metres in storms
Waves in the Andaman Sea and Gulf of Thailand are forecast to exceed three metres in areas experiencing thunderstorms, the TMD warned. Mariners in both sea areas should navigate cautiously and avoid sailing through thunderstorms.
Weather information is available around the clock through the TMD website or by calling 02-399-4012, 02-399-4013 or 1182.
The TMD scheduled its next warning for 5pm on October 22.
