The Interior Ministry has instructed governors of the southern provinces to prepare evacuation plans as the region is being battered by torrential rain.
Interior permanent secretary Grisada Boonrach said Monday the ministry has ordered the plans be devised as the Thai Meteorological Department has predicted heavy rain will likely continue over much of the South for around 10 more days.
Local public venues including city halls, schools and mosques will be turned into flood shelters for residents while local administrative authorities will work with the Provincial Electricity Authority and the Provincial Waterworks Authority to prevent electrocutions and drinking water shortages in communities.
Mr Grisada stressed the distribution of flood-relief bags must be conducted in accordance with state regulations to avoid complaints from residents.
Evacuation centres will be set up when needed. Local authorities can also seek additional money from the government to provide assistance for flood-affected residents if their existing funds are not sufficient, he added.
According to the Thai Meteorological Department, the downpours could trigger flash floods.
In its weather forecast for the southern provinces a strong northeasterly monsoon prevails over the Gulf of Thailand and the region while low pressure covers Malaysia and the lower South of Thailand.
On Monday, strong winds whipped waves up to 2-4 metres high in the Gulf of Thailand.
All ships should proceed with caution while small boats should remain in port at least until tomorrow, according to the department's warning.
Department of Disaster Prevention and Mitigation director-general Chatchai Phromlert said heavy rainfall last month caused widespread flooding across the South.
Many areas of 12 provinces in the region are still affected by floods, he said, with the 12 provinces stretching from Chumphon in the upper South right down to the far South in Yala, Pattani and Narathiwat.
More than 260,000 residents have already been affected by previous flooding which hit 689 tambons in 104 districts. There were 35 fatalities.
Currently, the flood situation has eased in Krabi, Ranong, Pattani, Prachuap Khiri Khan, Chumphon and Trang although the latest torrential rain could reverse the situation, Mr Chatchai warned.
In Surat Thani province, low-lying areas in Muang and Phunphin districts are still under water while Nakhon Si Thammarat's Pak Phanang, Hua Sai, Chian Yai, Chalerm Prakiat and Cha-uat districts have also been ravaged by severe flooding.
Mr Chatchai said department officials were working with the military to distribute basic necessities to villagers in flood-hit areas.
He said the department was monitoring weather conditions closely with rescue teams on standby.
The department was cooperating with state agencies to compile a list of flood-affected victims and their damaged property to provide them with compensation in line with Finance Ministry regulations, Mr Chatchai said.
In Yala, four houses were badly damaged in Bannang Sata district Monday after being hit by a landslide caused by heavy rainfall which has persisted since Friday. There were no casualties.
The military is providing help to affected residents.
Meanwhile, water from the Pattani and Sai Buri rivers overflowed into fruit and rubber farms as well as riverside homes.