Beach
Beach of Ueckermünde
Ueckermünde, Germany · sea 19.4 °C at its warmest, in August

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 24 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 Beach of Ueckermünde?
The sea off Beach of Ueckermünde averages 19.4 °C at its warmest, in August, and 1.7 °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 Beach of Ueckermünde?
The sea here never averages 20 °C in any month, so swimming means cold water all year. Some people do it anyway.
Where is Beach of Ueckermünde?
Beach of Ueckermünde is on the coast of Ueckermünde, Germany, at 53.7481, 14.0733. The map on this site flies straight to it.