BANGKOK—Heavy rain in northern, northeastern, and central Thailand worsened severe flooding in many parts of the country on Monday, as authorities ordered the release of water into already overflowing rivers from dams that were filled to capacity.
Many areas were already flooded from seasonal monsoon rains when the remnants of Tropical Storm Noru, which earlier tore through the Philippines and Vietnam, swept through parts of the country last week.
Among the areas hit by flooding were Chiang Mai, a large city and tourist center in the north, and Sukhothai, an ancient capital and archaeological site that draws many visitors.
The Department of Disaster Prevention and Mitigation reported that floods had impacted at least 45,000 households in 35 provinces.
In Chiang Mai, provincial disaster officials warned people with homes near the Ping River to move their property to higher ground, even as some areas were already inundated.
Officials also issued urgent flood warnings to residents of the north-central provinces of Sukhothai, Phitsanulok, and Phichit after the Yom River spilled over its banks.
In Ubon Ratchathani in the northeast, more than 7,000 people were moved into 60 shelters after the Moon River overflowed, as rescue workers waded through waist-high water to help residents evacuate.
In Nonthaburi province, just north of Bangkok, provincial authorities constructed a flood wall with more than 300,000 sand bags along about 10 kilometers (six miles) of the Chao Phraya River to try to prevent flooding from reaching key areas, Thai PBS public television reported on its website.