It was probably a rip tide... Pulled the boys away from shore. If that happens just swim WITH the current until it peters out... then swim to shore. If a person panics and tries to swim to shore before the rip ends - tries to swim ‘against current’ they usually drown.
Not necessarily a rip tide. Tide going out through a fairly narrow inlet creates a rush of water into the ocean from the IC, sound, river or what have you. Can’t speak for Jupiter but it’ll undermine the sand out from under your feet and make it difficult to stand or walk in knee deep water.
Every ocean swimmer should be given those instructions.
Rip tides terrify me.
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