Tens of thousands have been asked to evacuate from seaside towns and villages/ EPA
Tropical storm Pabuk has lashed southern Thailand with wind and rain, in what is expected to be the worst storm to hit the region in 30 years.
The storm made landfall at 12:45 local time (05:45 GMT), sending trees crashing down into houses in the province of Nakhon Si Thammarat, reports BBC.
It is moving across southern Thailand, affecting popular tourist spots.
Thousands of people have left Koh Samui, Koh Tao and Koh Phangan islands but many are riding out the storm.
At least two nearby airports on the mainland have been shut and ferry services have been suspended. Tourists stranded on Koh Samui have told the BBC that the island is seeing heavy rain, wind and waves and there have been short power cuts.
People also say they have been advised to stay indoors after 16:00 local time until Saturday morning.
"I talked to foreigners last night and they are not scared, they understand the situation," Krikkrai Songthanee, the district chief of neighbouring Koh Phangan, known for its raucous parties, told the AFP news agency.
He said 10,000 tourists were still on the island.