The Office of the National Water Resources (ONWR) is closely monitoring flooding in the deep South as water levels are expected to remain critical over the next few days, Surasee Kittimonthon, ONWR secretary-general, said on Wednesday.
Mr Surasee, also chairman of the Flood-Prone Area Water Management Centre in the Southern Region, said the flood situation in the southernmost provinces poses a concern as more downpours are forecast in many areas.
The local authorities are monitoring rainfall volumes in the Sukhirin and Waeng districts of Narathiwat, where floods have already devastated farmland and homes.
Mr Surasee said there have also been intense downpours in Muang, Bannang Sata, and Krong Pinang districts of Yala, as well as some areas in nearby Pattani.
People were evacuated from homes affected by floodwater after many were forced to climb onto their roofs and wait to be rescued.
As of Wednesday, the Bang Lang dam, a major water source located on the Pattani River in Yala, was storing 1,242.45 million cubic metres (m3) of water, which is 85% of its capacity. The dam, which is almost full, has limited capacity to take in more water and cushion the effect of the flooding as a result.
Mr Surasee said the floods are predicted to begin subsiding over the New Year weekend.
Eight districts in Pattani, covering 30 tambons and 95 villages, were declared disaster areas on Wednesday.
The eight districts were Kapho, Khok Pho, Mai Kaen, Muang, Nong Chik, Sai Buri, Thung Yang Daeng, and Yarang, where the floods affected at least 25,000 people from 8,360 families.
In Narathiwat, 158,126 people from 41,442 families across 13 districts -- Bacho, Chanae, Cho Airong, Muang, Rangae, Rueso, Sri Sakhon, Sukhirin, Sungai Kolok, Sungai Padi, Takbai, Waeng, and Yi-ngo -- have been affected by the floods.
Seven people were reported to have died as a result of the flooding -- three in Rangae district and four in Rueso district.
On Tuesday, Prime Minister and Finance Minister Srettha Thavisin travelled to Narathiwat to see first-hand the flooding situation in the southern region.