Beach
Praia da Samarra
São João das Lampas e Terrugem, Portugal · sea 18.7 °C at its warmest, in August

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 Praia da Samarra?
The sea off Praia da Samarra averages 18.7 °C at its warmest, in August, and 14.4 °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 Praia da Samarra?
The sea here never averages 20 °C in any month, so swimming means cold water all year. Some people do it anyway.
Where is Praia da Samarra?
Praia da Samarra is on the coast of São João das Lampas e Terrugem, Portugal, at 38.8969, -9.4350. The map on this site flies straight to it.
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