BANGKOK, Thailand – Thailand’s Meteorological Department has issued its 11th severe weather warning as heavy to very heavy rain continues to hit large parts of the country, with strong winds and dangerous waves expected across the Andaman Sea through the coming days. Authorities identified Ranong, Phang Nga, Chanthaburi, and Trat as high-risk provinces on May 18, while several northern, northeastern, and central provinces also remain under moderate weather alerts as monsoon conditions intensify.
Meteorologists warned that persistent rainfall and accumulated water could trigger flash floods, forest runoff, and overflowing rivers, especially in low-lying areas and locations near hillsides and waterways. Residents have also been advised to monitor their health as rapidly changing weather conditions continue across the country. The southwest monsoon covering the upper Andaman Sea and Thailand has strengthened considerably, bringing rough sea conditions. Waves in the upper Andaman Sea are expected to reach 2–3 meters, with heights exceeding 3 meters during thunderstorms. Smaller vessels in the upper Andaman Sea have been advised to remain ashore between May 17 and 22.
Authorities also warned boat operators in both the Andaman Sea and Gulf of Thailand to navigate with extreme caution and avoid storm areas due to the risk of sudden high waves and strong winds.
The weather department said heavy rainfall would likely continue between May 18 and 22 across the North, upper Northeast, Central Plains, East, and South before gradually easing later in the week as the monsoon weakens slightly.
Despite widespread rain, temperatures across Thailand remain extremely hot and humid. The country’s highest temperature on May 17 reached 39.7°C in Thoen district of Lampang, highlighting the unstable mix of heat and tropical storm activity affecting the region. Meanwhile, officials also reported several moderate earthquakes between May 16 and 17 centered in Vietnam, Myanmar, and India’s Andaman Islands, though authorities confirmed there was no impact on Thailand.
