Heavy Rain Warning Issued for 43 Thai Provinces
Thailand's meteorological department issued a heavy rain warning for 43 provinces on August 11, with the strongest impacts expected in the north and northeast where thunderstorms could trigger flash floods in low-lying areas and near waterw
On August 11, 2025, the Thai Meteorological Department forecast heavy rainfall in scattered areas across upper Thailand over the next 24 hours. A monsoon trough is moving across the upper northern and upper northeastern regions toward a low-pressure system in northern Vietnam, while the southwestern monsoon covering the Andaman Sea and Thailand's coastal areas is moderately strong.
Residents in affected areas are warned to watch for dangers from heavy and accumulated rainfall, which may cause flash floods and flash flooding, especially in foothill areas near waterways and in low-lying zones.
Waves in the upper Andaman Sea and upper Gulf of Thailand are moderately strong, reaching 2–3 meters in height, with waves exceeding 3 meters in thunderstorm areas. Boat operators are urged to exercise caution and avoid thunderstorm zones. Small boats in the upper Andaman Sea and upper Gulf of Thailand should remain ashore.
**Northern Region**: Thunderstorms in 70% of the area with heavy rain in some places. Affected provinces include Mae Hong Son, Chiang Mai, Chiang Rai, Lampang, Phayao, Nan, Uttaradit, Tak, Phichit, and Phetchabun. Low 23–27°C, high 31–34°C. Southwest winds 10–20 kph.
**Northeastern Region**: Thunderstorms in 70% of the area with heavy rain in some places. Affected provinces include Nong Khai, Bueng Kan, Udon Thani, Sakon Nakhon, Nakhon Phanom, Mukdahan, Yasothon, Amnat Charoen, Nakhon Ratchasima, Buriram, Surin, and Ubon Ratchathani. Low 24–25°C, high 32–34°C. Southwest winds 10–20 kph.
**Central Region**: Thunderstorms in 60% of the area with heavy rain in some places. Affected provinces include Uthai Thani, Lopburi, Saraburi, Kanchanaburi, and Ratchaburi. Low 24–26°C, high 32–34°C. Southwest winds 10–25 kph.
**Eastern Region**: Thunderstorms in 70% of the area with heavy rain in some places. Affected provinces include Nakhon Nayok, Prachuap Khiri Khan, Chachoengsao, Chanthaburi, and Trat. Low 24–27°C, high 30–34°C. Southwest winds 20–40 kph. Seas with 2–3 meter waves, exceeding 3 meters in thunderstorm areas.
**Southern Region (East Coast)**: Thunderstorms in 40% of the area. Mostly in Phetchaburi, Prachuap Khiri Khan, Chumphon, Songkhla, Pattani, Yala, and Narathiwat. Low 23–25°C, high 32–35°C. Southwest winds 20–35 kph. Seas with 1–2 meter waves, exceeding 2 meters offshore and in thunderstorm zones.
**Southern Region (West Coast)**: Thunderstorms in 40% of the area. Ranong, Krabi, Trang, and Satun provinces. Low 24–28°C, high 31–34°C. From Phang Nga northward: southwest winds 20–40 kph, waves 2–3 meters, exceeding 3 meters in thunderstorms. From Phuket southward: southwest winds 20–35 kph, waves around 2 meters, exceeding 2 meters in thunderstorms.
**Bangkok and Vicinity**: Thunderstorms in 70% of the area with heavy rain in some places. Low 26–27°C.