Isolated downpours forecast for most of Thailand

Heavy rainfall is expected in every region except the North, it said.

Flash flooding and overflowing waterways near foothills and low-lying areas are a major concern, the department said, adding that motorists should drive cautiously during thundershowers.

Waves will average between one and two metres in height in the upper Andaman Sea and the upper Gulf of Thailand, but could exceed two metres in height during thundershowers due to the moderate southwest monsoon in the area, the department said. All ships should proceed with caution and avoid thundershowers, it advised.

The department provided the following list of provinces that will be hit by heavy rain:

North: Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Nan, Phrae, Uttaradit, Sukhothai, Tak, Kamphaeng Phet, Phitsanulok, Phichit, and Phetchabun.

Northeast: Loei, Nong Khai, Nong Bua Lamphu, Udon Thani, Chaiyaphum Khon Kaen, Maha Sarakham, Nakhon Ratchasima, and Buriram.

Central: Nakhon Sawan, Uthai Thani, Chainat, Singburi, Ang Thong, Lopburi, Saraburi, Phra Nakhon Si Ayutthaya, Kanchanaburi, and Bangkok metropolitan area.

East: Nakhon Nayok, Prachinburi, Chachoengsao, Chanthaburi and Trat.

South: Chumphon, Surat Thani and Nakhon Si Thammarat, Ranong, Phang Nga, and Krabi.