Seemingly out of nowhere, though, lightning struck.
The 19-year-old guard fell out of his chair and the force knocked a nearby group of people to the ground around 4:30 p.m. at the 21st Avenue Beach, witnesses tell CBS2.
A visitor recalls it smelling like hair burning.
As suddenly as the lightning came down from the sky, Pinto -- a former Toms River High School North track runner and dear friend to many -- was gone.
Seven other struck -- including four guards -- were treated at area hospitals.
More than $7,300 had been raised as of Tuesday morning on a GoFundMe to honor Pinto.
"Words cannot describe how so many of us are feeling right now. We lost a special guy tonight, one who was so close and meant so much to so many people," campaign founder Chase Vander Vliet writes.
"A complete tragedy that nobody would have ever expected to happen. It would be impossible to get it all into words how much our friend meant to us but we all know how amazing he was.
"Keith has left behind an overwhelming amount of amazing memories that will live in our hearts forever. All donations will go directly to Keith’s family for the proper goodbye that he deserves. Our hearts are broken by what happened and all our love and support goes out to the Pinto family and all others affected by this tragedy. We’re gonna miss you so much brother❤️#LLK."
Berkeley Township Mayor Carmen Amato said the incident was tragic and heartbreaking.
"This person was out there every day protecting the lives of others," he said. "Our lifeguard teams, like so many others along the shore, develop special connections with our community throughout the summer which makes this loss even greater."
The mayor offered condolences to the families affected and community at large.
The township's beaches will be closed to swimmers until Friday. Grief counseling will be offered.
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