River & lake beach
Poço Dos Chefes
Curral das Freiras, Portugal · sea 23.7 °C at its warmest, in September

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 14 km offshore, at the nearest open water cell of a 0.25° grid.
About
River beach in Curral das Freiras, Madeira
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 Poço Dos Chefes?
The sea off Poço Dos Chefes averages 23.7 °C at its warmest, in September, and 17.9 °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 Poço Dos Chefes?
The sea reaches 20 °C or more from June to November. Twenty degrees is where most swimmers stop calling water cold; below it, a wetsuit helps.
Where is Poço Dos Chefes?
Poço Dos Chefes is on the coast of Curral das Freiras, Portugal, at 32.7176, -16.9690. The map on this site flies straight to it.