Swimmers are seen around a river with a low cliff, where many have gathered to jump off into the water below.

Hot outside? Here's why taking an ice-cold plunge could be deadly

Just because there's a heat wave, it doesn't mean the water is warm. Here's what boaters and swimmers should be aware of before they take a dip.

Cliff divers line up along the Clackamas River at High Rocks Park during a heatwave in June 2021 in Portland, Oregon.
Photograph by Nathan Howard, Getty Images
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