Officials urged people to conserve electricity to ease strain on the state's power grid and, in an effort to prevent a surge in coronavirus cases, to follow physical distancing and mask requirements when they hit recreational areas.
By 8 a.m. Saturday, a parking lot near the Manhattan Beach pier was already full as visitors arrived early to secure a spot.
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All beaches in Los Angeles and Orange County are scheduled to remain open throughout the holiday weekend, officials said, but they warned that they could be shut down if there's overcrowding.
"My inkling is we will have a lot of people because you can't really travel, and the next best thing to a Hawaiian beach vacation is an LA beach staycation," said Pono Barnes, a spokesman for Los Angeles County lifeguards, who patrol 72 miles of coastline.
Masks are required on all L.A. County beaches except for when you're in the water, but in Santa Monica, many were seen without one. In that city, those without a mask can be fined $100.