"Meteorological Department" issued Announcement No. 10 warns of heavy to very heavy rain in upper Thailand, listing provinces at risk of flash floods and rapid runoff.
20 August 2026 GMT+7Meteorological DepartmentAnnouncement No. 10 on heavy to very heavy rain in upper Thailand is effective until 21 August 2026. It states that Thailand is experiencing some heavy to very heavy rain, especially in the northern and northeastern regions. This is due to the monsoon passing through the north and upper northeast, combined with a fairly strong southwest monsoon covering the Andaman Sea, Thailand, and the Gulf of Thailand.
Residents in these areas are urged to be cautious of hazards from heavy to very heavy rain and accumulated rainfall, which may cause flash floods and rapid runoff, particularly in foothill areas near waterways and low-lying zones. Avoid traveling through frequently flooded routes, especially lowlands where short-term flooding may occur.
The seas in the upper Andaman and upper Gulf of Thailand have fairly strong winds with waves 2-3 meters high; in areas with thunderstorms, waves exceed 3 meters. The lower Andaman Sea has waves about 2 meters high, rising above 2 meters with storms. Mariners in the Andaman Sea and Gulf of Thailand are advised to navigate cautiously and avoid sailing in stormy areas. Small boats in the upper Andaman and upper Gulf of Thailand should avoid leaving shore during this period.
For safety and to minimize potential impacts, residents are advised to plan daily activities and travel carefully during this time. Please continue to follow announcements from the Meteorological Department and access information at their website http://www.tmd.go.th or by calling 0-2399-4012-13 and 1182, available 24 hours.
20 August 2026 GMT+7
21 August 2026 GMT+7
