There are usually quite a few people on the Tri Trang Beach from February to November.
The air temperature at Tri Trang Beach allows sunbathing all year round. There may be some who find the water at Tri Trang Beach too warm.
From April to December Tri Trang Beach has rainy season. This is something to keep in mind when planning your trip since it is quite possible that you may be unable to sunbathe.