This is the dramatic moment a flood-stricken resident was found battling to stay alive on a tin roof as raging floods swept across southern Thailand.

The exhausted villager, 60, had hauled himself onto a shop awning as the deluge engulfed Songkhla province, on November 26.

He lay motionless next to a shop signage as the muddy floodwater lapped at the tin roof beneath him.

Passing volunteers later found the man sprawled helplessly on the structure, with nearby residents frantically waving for help.

Footage shows the team gripping power cables for balance as they hoisted the man onto their boat.

Neighbours said they spotted the man being swept away in the fast-moving currents. They pulled him to safety using a lifebuoy tied to a rope, but he reportedly collapsed after clambering onto the roof.

Rescuer Kittipoom Chantachot said: 'The residents were the first to rescue him. Luckily, we happened to pass by and were able to help. The man no longer had the strength to even stand up. He could have died if no rescuers came.'

He added that the villager was taken to a hospital for treatment.

The death toll has climbed to 33 as catastrophic floods, described by Prime Minister Anutin Charnvirakul as 'the worst flooding in 15 years', swept through southern Thailand.

Government spokesman Siripong Angkasakulkiat said: 'There have been 33 deaths across seven provinces. Causes of death include being swept away by currents, drowning, electrocution, and landslides.'

Soldiers, volunteers, and local government units have also been mobilised to hasten relief efforts, but they were hobbled by limited phone signal in the area.

The Thai military has sent some 200 boats, 20 helicopters and its lone aircraft carrier, the Chakri Naruebet, to deliver essential supplies and carry out rescue efforts.

Songkhla's Hat Yai district was among the worst-hit areas, which saw a record 13 inches (335 mm) of rain in a single day on November 21.

Songkhla Governor Ratthasart Chidchoo on Monday declared all 16 districts disaster zones and ordered the immediate evacuation of children, the elderly and the sick.

On Sunday, high-clearance trucks arrived to evacuate more than 400 tourists from flooded hotels across the city.

The Disaster Prevention and Mitigation Department said that floods hit nine southern provinces, affecting some 1,128,284 households and 3,221,958 people.

The Southern Eastern Meteorological Centre said a strong monsoon trough was causing the heavy rainfall, which was expected to ease this week.

Thailand and neighbouring countries in Southeast Asia are in their annual monsoon rainy season which sees soaring temperatures followed by powerful rain storms in the afternoon leading to widespread flash floods.