Residents of Tak, Mae Hong Son, Chiang Mai, and Chiang Rai have been readied for evacuation.

An Andaman Sea storm has brought heavy rainfall in the North, according to meteorologist Worapong Khunawattanangkul.

In Chiang Rai, disaster-prone Mae Fa Luang, Mae Chan, Mae Suay, Mae Sai and Wiang Pa Pao districts were told to evacuate if rainfall exceeds 100 millimetres.

They were at extreme risk of landslides and flash floods, according to local disaster-prevention chief Suthep Dechchaisri. There had been more than 70 reports of subsiding hill-country land in Tak border areas, including Mae Ramat, Ban Tak, Tha Song Yang and Mae Sot districts. They would be declared disaster zones.

Two houses in Umphang district were swallowed by a three-metre-deep sinkhole, a local official reported.

In central Thailand, six villages along the Prachantakham canal in Prachin Buri were submerged by floodwater from the nearby Khao Yai National Park.

Meanwhile, the body of Mae Hong Son flood victim Manit Panta was found three kilometres from his home. He was swept away on Wednesday.