Golden sand
Isuntza
Lekeitio, Spain · sea 22.1 °C at its warmest, in August

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020.
About
La playa Isuntza situada en el municipio vizcaíno de Lequeitio, País Vasco (España), es una playa con arena oscura situada junto al puerto y el parque del municipio.
Questions
How warm is the sea at Isuntza?
The sea off Isuntza averages 22.1 °C at its warmest, in August, and 12.4 °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 Isuntza?
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 Isuntza?
Isuntza is on the coast of Lekeitio, Spain, at 43.3628, -2.5006. The map on this site flies straight to it.