Heavy Rain Sweeps Thailand, 35 Provinces on Alert
A monsoon trough and southwest monsoon system are bringing heavy rain to 35 Thai provinces through August 7, with warnings issued for flooding and dangerous sea conditions in the Andaman Sea and Gulf of Thailand.
The Thai Meteorological Department issued a weather forecast on August 6, 2025, for the next 24 hours, predicting heavy to very heavy rain across the northern, northeastern, eastern, and western southern regions. The severe weather is caused by a monsoon trough moving through northern Thailand and Laos, combined with a strong southwest monsoon system affecting the Andaman Sea, Thailand, and the Gulf of Thailand. The public is warned to be cautious of heavy rainfall, accumulated water, sudden flooding, and flash floods, especially in foothill areas near watercourses and low-lying zones.
Wave conditions in the upper Andaman Sea are strong, with heights of 2-4 meters, exceeding 4 meters during thunderstorms. The upper Gulf of Thailand has wave heights of 2-3 meters, exceeding 3 meters during storms. Mariners are advised to exercise caution and avoid areas with thunderstorms, while small boats in the upper Andaman Sea and upper Gulf should stay ashore.
Tropical storm Koujira remains in the upper southern South China Sea, west of the Philippines. Those planning to travel to the region should check weather conditions beforehand, as the storm is not expected to enter Thailand.
Regional forecasts from 6:00 AM today to 6:00 AM tomorrow:
Northern Region: Thunderstorms in 70% of the area with heavy rain in some places, particularly in Chiang Mai, Lampang, Phrae, Tak, Uttaradit, Phichit, and Phetchabun, with very heavy rainfall in parts of Chiang Rai, Phayao, and Nan. Low 23-26°C, high 29-35°C. Southwest winds 10-20 km/h.
Northeastern Region: Thunderstorms in 70% of the area with heavy rain in places like Udon Thani, Kalasin, Mukdahan, Roi Et, Yasothon, Amnat Charoen, Sisaket, and Ubon Ratchathani, with very heavy rainfall in Nong Khai, Bueng Kan, Sakon Nakhon, and Nakhon Phanom. Low 23-24°C, high 28-34°C. Southwest winds 10-20 km/h.
Central Region: Thunderstorms in 70% of the area with heavy rain in Lopburi and Kanchanaburi. Low 23-26°C, high 35-38°C. Southwest winds 10-25 km/h.
Eastern Region: Thunderstorms in 70% of the area with heavy rain in Nakhon Nayok, Prachuap Khiri Khan, and Rayong, with very heavy rainfall in Chanthaburi and Trat. Low 22-27°C, high 29-34°C. Southwest winds 20-40 km/h. Sea waves 2-3 meters, exceeding 3 meters in thunderstorm areas.
Southern Region (East Coast): Thunderstorms in 40% of the area with heavy rain in Prachuap Khiri Khan, Chumphon, and Surat Thani. Low 24-26°C, high 32-35°C. Southwest winds 20-35 km/h. Sea waves 1-2 meters, exceeding 2 meters offshore and in thunderstorm areas.
Southern Region (West Coast): Thunderstorms in 60% of the area with heavy rain in Phuket, and very heavy rainfall in Ranong and Phang Nga. Low 23-27°C, high 29-34°C.