The Meteorological Department issued Bulletin No. 10 warning of heavy to very heavy rain in Thailand, advising caution against flash floods and sudden torrents affecting the country until 18 May 2026 GMT+7.
On 17 May 2026 GMT+7, the Meteorological Department announced Bulletin No. 10 regarding heavy to very heavy rain in Thailand and strong waves in the Andaman Sea, effective until 18 May 2026 GMT+7.
It stated that northern Thailand will experience localized heavy rain, mostly in the west and upper northeastern regions. Some areas in the western and eastern parts of southern Thailand will have heavy to very heavy rain. Residents in these areas are advised to be cautious of dangers from heavy and accumulated rainfall that may cause flash floods and sudden torrents, especially in foothill areas, near waterways, and low-lying zones. This is due to a relatively strong southwest monsoon covering the Andaman Sea, Thailand, and the Gulf of Thailand. People should also take care of their health amid changing weather conditions.
The seas in the Andaman Sea and Gulf of Thailand are experiencing fairly strong winds. In the upper Andaman Sea from Phuket province northwards, waves range from 2 to 3 meters high, exceeding 3 meters in areas with thunderstorms. In the lower Andaman Sea from Krabi province southwards and the upper Gulf of Thailand, waves reach about 2 meters high, exceeding 2 meters in thunderstorm zones. Mariners in these areas are urged to navigate cautiously and avoid sailing in stormy conditions. Small boats in the upper Andaman Sea are advised to remain in port.
From 19 to 22 May 2026 GMT+7, rainfall is expected to increase, with heavy to very heavy rain in some places, mainly in the western regions, north, upper northeast, east, and western southern Thailand. This is due to a low-pressure area over the Mottama Gulf in Myanmar intensifying, combined with a relatively strong southwest monsoon covering the Andaman Sea, Thailand, and the Gulf of Thailand.
The public is urged to follow updates from the Meteorological Department and can access information on its website.http://www.tmd.go.thor call 0-2399-4012-13 and 1182, available 24 hours.
Announcement issued on 17 May 2026 GMT+7 at 17:00.
The Meteorological Department will issue the next bulletin on 18 May 2026 GMT+7 at 05:00.