Beach
Back Beach
Western Australia, Australia · sea 23.6 °C at its warmest, in March

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 Back Beach?
The sea off Back Beach averages 23.6 °C at its warmest, in March, and 19.3 °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 Back Beach?
The sea reaches 20 °C or more from January, February, March, April, May, June, July, November and December. Twenty degrees is where most swimmers stop calling water cold; below it, a wetsuit helps.
Where is Back Beach?
Back Beach is on the coast of Western Australia, Australia, at -28.7942, 114.6111. The map on this site flies straight to it.