Beach
Playa de San Julián (Liendo)
Liendo, Spain · sea 21.7 °C at its warmest, in August

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 20 km offshore, at the nearest open water cell of a 0.25° grid.
About
La playa de San Julián está situada en el municipio de Liendo, en la comunidad autónoma de Cantabria, España.
Questions
How warm is the sea at Playa de San Julián (Liendo)?
The sea off Playa de San Julián (Liendo) averages 21.7 °C at its warmest, in August, and 12.5 °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 Playa de San Julián (Liendo)?
The sea reaches 20 °C or more from July to September. Twenty degrees is where most swimmers stop calling water cold; below it, a wetsuit helps.
Where is Playa de San Julián (Liendo)?
Playa de San Julián (Liendo) is on the coast of Liendo, Spain, at 43.4127, -3.3706. The map on this site flies straight to it.