Thailand's Meteorological Department warns of heavy rain across northern and northeastern regions from July 8–9, intensifying nationwide July 10–14 with risks of flash floods and dangerous waves in the Andaman Sea and Gulf of Thailand.
On July 8, 2025, the Thai Meteorological Department issued a 7-day weather forecast for July 8-14, 2025. During July 8-9, heavy rain is expected in parts of the Northern Region, upper Northeastern Region, and Eastern Region due to a low-pressure system covering northern Vietnam combined with moderate southwest monsoon winds over the Andaman Sea, Thailand, and the Gulf of Thailand. Waves in the Andaman Sea and Gulf of Thailand are moderate, with the upper Andaman Sea experiencing waves around 2 meters high, the lower Andaman Sea and upper Gulf of Thailand at 1-2 meters, and thunderstorm areas seeing waves exceeding 2 meters.
From July 10-14, rainfall will increase with heavy downpours in the upper Northeastern Region, Eastern Region, and western coastal Southern Region. A monsoon trough will move across Myanmar, Laos, and northern Vietnam, strengthening the southwest monsoon winds over the Andaman Sea, Thailand, and the Gulf of Thailand. Waves will intensify, with the upper Andaman Sea experiencing 2-4 meter waves and thunderstorm areas exceeding 4 meters, while the upper Gulf of Thailand will see 2-3 meter waves with thunderstorm areas exceeding 3 meters.
Typhoon Baohui, located east of the Philippines, is expected to pass through Taiwan and make landfall on China's eastern coast around July 11-12, 2025, and will not affect Thailand. Travelers to those areas should check weather conditions before departing.
Warnings: During July 10-14, residents of Thailand—especially in the Northern, Northeastern, Eastern, and western coastal Southern regions—should be alert to dangers from heavy and accumulated rainfall, which may cause flash floods, flash floods, and riverbank overflows, particularly in sloped terrain near water channels and low-lying areas. Fishermen in the Andaman Sea and Gulf of Thailand should navigate with caution and avoid thunderstorm areas. Small boats in the Andaman Sea and upper Gulf of Thailand should avoid sailing between July 10-14 due to strong waves. Coastal residents of the western Southern Region should beware of dangerous wave surges.
Regional forecast for July 8-14:
Northern Region: July 8-9 will see thunderstorms affecting 40-60% of areas with heavy rain in some places. July 10-14 will have thunderstorms in 60-70% of areas with heavy downpours. Southwest winds at 10-20 km/h, low 24-27°C, high 30-36°C.
Northeastern Region: July 8-9 will see thunderstorms affecting 30-40% of areas with heavy rain in some places. July 10-14 will have thunderstorms in 60-70% of areas with heavy downpours, especially heavy on July 12-13. Southwest winds at 10-25 km/h, low 23-27°C, high 28-35°C.
Central Region: July 8-9 will see thunderstorms affecting 20-40% of areas. Southwest winds at 10-25 km/h. July 10-14 will have thunderstorms in 60-70% of areas with heavy rain.