If you're not someone with firsthand knowledge of swimming in the San Francisco Bay area, then there's probably another element to these dips that has escaped you: the drama over whether to don a wetsuit while taking one. As Robert McMillan writes for the Wall Street Journal, a "great wetsuit divide" exists among the Bay's swimmers. Some see wearing the so-called "wuss suit" as cheating and refuse to do so; others see them as a valuable protection against the cold—water and air temps are in the 50s right now. And as a 2018 SFGate article pointed out, the ocean temperatures off Northern California's coast are actually colder than Alaska's in the summer due to upwelling, in which super-cold water rises from the ocean's depths to the surface.
To get the never-wetsuit perspective, McMillan talks to Tom Linthicum, who has completed the 1.25-mile swim from Alcatraz to San Francisco some 200-plus times, always sans wetsuit. In his view, "you’re not really enjoying the cold" if you're in one. As Linthicum explains, the "bone-numbing cold of the water is the whole point, and never something to be avoided." Adele Gower is an inbetweener: She used to wear a wetsuit during her 90-minute Bay swims. But she says she grew tired of the shaming and ditched it, but has had to trim her swims to 30 minutes, as that's all she can bear. (Read the full article for more on the quirky divide).