Storm warnings for Samui and Southern Thailand (East and West coasts).
 

Here is the warning given by the Thai Met Office.

Tropical storm “PABUK” over the lower Gulf has its maximum sustained winds of 75 km/hr and is moving west-northwest slowly expectedly to make landfall evening 4 January over Nakhon Si Thammarat. By 3-5 January 2019, it will affect widespread rains with torrential downpours much of the South east coast. People beware of the severe conditions. The strong winds are forecast with waves up to 3-5 meters high in the Gulf and 2-3 meters high in the Andaman sea. All ships in the Gulf keep ashore lasting 5 January 2019. The strong high-pressure system still covers upper Thailand with cool to cold spells. People are advised to keep healthy"

Any travelling in the region should be aware that many flights and ferry services have been cancelled.
There is also a risk of damage, storm surge and inundation in coastal areas on islands and mainland.