Beach
Spiaggia di Porto Frailis
Tortolì, Italy · sea 26.2 °C at its warmest, in August

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 16 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 Spiaggia di Porto Frailis?
The sea off Spiaggia di Porto Frailis averages 26.2 °C at its warmest, in August, and 13.9 °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 Spiaggia di Porto Frailis?
The sea reaches 20 °C or more from June to October. Twenty degrees is where most swimmers stop calling water cold; below it, a wetsuit helps.
Where is Spiaggia di Porto Frailis?
Spiaggia di Porto Frailis is on the coast of Tortolì, Italy, at 39.9244, 9.7051. The map on this site flies straight to it.