Beach
Playa de Merón (San Vicente de la Barquera)
San Vicente de la Barquera, Spain · sea 21.4 °C at its warmest, in August

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 26 km offshore, at the nearest open water cell of a 0.25° grid.
About
El Sable de Merón o playa de Merón es una playa situada en el municipio de San Vicente de la Barquera, en la comunidad autónoma de Cantabria, España. Dispone de acceso a discapacitados.
Questions
How warm is the sea at Playa de Merón (San Vicente de la Barquera)?
The sea off Playa de Merón (San Vicente de la Barquera) averages 21.4 °C at its warmest, in August, and 12.6 °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 Merón (San Vicente de la Barquera)?
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 Merón (San Vicente de la Barquera)?
Playa de Merón (San Vicente de la Barquera) is on the coast of San Vicente de la Barquera, Spain, at 43.3907, -4.3803. The map on this site flies straight to it.