Beach
Karon Noi Beach
Karon, Thailand · sea 29.9 °C at its warmest, in May

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 17 km offshore, at the nearest open water cell of a 0.25° grid.
Wikipedia has no article about this beach yet. It is on the atlas from its Wikidata record and its photograph.
Questions
How warm is the sea at Karon Noi Beach?
The sea off Karon Noi Beach averages 29.9 °C at its warmest, in May, and 28.4 °C at its coolest. These are monthly means from NOAA's OISST v2.1 satellite and buoy record for 1991 to 2020, sampled at the beach's own coordinates.
When can you swim at Karon Noi Beach?
The sea reaches 20 °C or more from All year. Twenty degrees is where most swimmers stop calling water cold; below it, a wetsuit helps.
Where is Karon Noi Beach?
Karon Noi Beach is on the coast of Karon, Thailand, at 7.8649, 98.2825. The map on this site flies straight to it.