BANGKOK: Heavy rain is expected in parts of northern, northeastern and eastern Thailand, while Bangkok and neighbouring provinces face thunderstorms across 60% of the area, according to the Thai Meteorological Department.
The department warned residents in upper Thailand to remain alert for heavy and accumulated rainfall that could trigger flash floods and forest run-off, particularly near foothills, waterways and low-lying areas.
The unsettled conditions are being driven by a moderate southwest monsoon covering the Andaman Sea, Thailand and the Gulf of Thailand, together with a low-pressure area over upper Vietnam. Rainfall in the South is expected to ease.
Heavy rain is possible in 36 provinces, including Mae Hong Son, Tak, Phitsanulok and Phetchabun in the North.
In the Northeast, affected areas include Bueng Kan, Sakon Nakhon, Nakhon Phanom, Mukdahan, Amnat Charoen and Ubon Ratchathani.
Rain is also expected across parts of the Central region, including Nakhon Sawan, Uthai Thani, Chai Nat, Suphan Buri, Ayutthaya, Saraburi, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Songkhram and Samut Sakhon, as well as Bangkok and surrounding provinces.
Eastern provinces likely to be affected include Nakhon Nayok, Prachin Buri, Chanthaburi and Trat.
In the South, rain is expected in Chumphon, Surat Thani, Nakhon Si Thammarat, Pattani, Yala, Narathiwat, Ranong, Phang Nga, Phuket and Krabi.
Bangkok faces storms across 60% of the area
Bangkok and its surrounding provinces are expected to experience thunderstorms across 60% of the area. Temperatures will range from 26-28 degrees Celsius in the morning to highs of 33-35°C, with southwesterly winds of 10-20 kilometres per hour.
The eastern region also has a 60% chance of thunderstorms, with heavy rain possible in Nakhon Nayok, Prachin Buri, Chanthaburi and Trat. Temperatures are expected to range from 23-28°C to highs of 31-34°C.
The North and Northeast each have a 40% chance of thunderstorms, with isolated heavy rain. Northern temperatures will range from 23-25°C to highs of 32-35°C, while the Northeast will see lows of 23-26°C and highs of 33-35°C.
The Central region has a 40% chance of thunderstorms, mainly in its western and upper areas. Temperatures will reach 34-36°C after morning lows of 24-26°C.
Mariners warned of waves above two metres
Waves in the upper Andaman Sea and upper Gulf of Thailand are expected to reach about two metres, while the lower Andaman Sea and lower Gulf will see waves of one to two metres.
Waves may rise above two metres during thunderstorms. Mariners have been advised to proceed cautiously and avoid areas affected by storms.
The southern east coast has a 30% chance of thunderstorms, mainly in Chumphon, Surat Thani, Nakhon Si Thammarat, Pattani, Yala and Narathiwat.
The southern west coast has a 40% chance of thunderstorms, mainly in Ranong, Phang Nga, Phuket and Krabi.
The forecast covers the period from 6am on July 16 to 6am on July 17, 2026. - The Nation/ANN
