Beach
Mateo Coast State Beaches
San Mateo County, United States · sea 14.9 °C at its warmest, in August

Sea temperature month by month
Monthly means in °C, NOAA OISST v2.1 climatology 1991–2020, sampled 13 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 Mateo Coast State Beaches?
The sea off Mateo Coast State Beaches averages 14.9 °C at its warmest, in August, and 12 °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 Mateo Coast State Beaches?
The sea here never averages 20 °C in any month, so swimming means cold water all year. Some people do it anyway.
Where is Mateo Coast State Beaches?
Mateo Coast State Beaches is on the coast of San Mateo County, United States, at 37.4778, -122.4494. The map on this site flies straight to it.
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