Troops across the country will sweep into flood-hit southern provinces if the crisis proves too much for the Fourth Army Region to handle.
Army chief Gen Prayuth Chan-ocha said tens of thousands of soldiers from other regions will be sent to assist in flood rescue and relief operations if the situation worsens.
He said the Fourth Army Region, which oversees the South, has set up a flood relief centre.
"It looks scary but the Fourth Army commanders assure us the situation is still under control," he said.
About 10,000 troops are being deployed to help the flood victims in nine provinces, he said.
Prayuth: Thousands of troops stand readyGen Prayuth said his prime concern is persistent rain which would cause mountain runoff, increase the risk of mudslides and slow flood drainage to the sea.
"The hardest-hit areas are Khao Luang mountain in Nakhon Si Thammarat and Surat Thani. Let's hope the rain stops soon," he said.
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Nakhon Si Thammarat has declared 14 districts disaster zones, with 124,000 people affected, and estimated the damage at 120 million baht.
The flood situation in Muang municipality of Nakhon Si Thammarat improved slightly yesterday after rain stopped.
The floodwater in several communities has started to recede, which helped rescue and relief operations.
In Lan Saka district, 52 tourists who were stranded at a resort in tambon Khiri Wong were rescued.
In Nop Phi Tham and Si Chon districts, several communities remained cut off after bridges were damaged.
Troops and volunteers built makeshift bridges so food and water could be sent across.
Meanwhile, Phatthalung authorities issued landslide warnings for 28 locations in six districts ravaged by flooding, even though overall water levels had subsided.
In some areas of Khuan Khanun, Pak Phayun and Muang districts, the floodwater was as high as 1.5 metres.
In Chumphon, floodwater on a stretch of Asian Highway 41 receded yesterday, which allowed vehicles to use the route again. Police were deployed to help direct traffic.
Flooding has also hit five districts in Chumphon province, causing 50 million baht in damage.
Meanwhile, the Meteorological Office yesterday issued a heavy rain warning for Chumphon, Surat Thani and Nakhon Si Thammarat. Waves of up to 3m are expected in the Gulf of Thailand and small boats should remain ashore from tomorrow until Sunday, it said.
The Ministry of Industry is now surveying the storm-hit southern region, said deputy government spokesman Chalitrat Chandrubeksa.
Between Sunday and yesterday, eight factories in Songkhla's Sadao and Hat Yai districts were damaged by heavy rain and flash floods.
Most were only slightly damaged, except for the Safeskin Corporation (Thailand) Co complex in Hat Yai which houses about 900 employees.
It suffered around 100 million baht in damage.
There are 194 factories, 30 community enterprises and six mines and crushing plants located in Chumphon's flood-hit Sawi, Thung Tako, Lang Suan, Lamae and Phato districts.