Beach
Praia Velha
Oeiras e São Julião da Barra, Paço de Arcos e Caxias, Portugal · sea 18.8 °C at its warmest, in September

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020.
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 Velha?
The sea off Praia Velha averages 18.8 °C at its warmest, in September, and 14.6 °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 Praia Velha?
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 Velha?
Praia Velha is on the coast of Oeiras e São Julião da Barra, Paço de Arcos e Caxias, Portugal, at 38.6930, -9.2914. The map on this site flies straight to it.
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