"The very hot conditions through Labor Day will bring an increased threat of large fire activity including fires with large vertical growth,'' the National Weather Service tweeted. Woodland Hills is forecast to hit highs 117 degrees Sunday, according to the agency.
One of the county's cooling center's is located at Ruben F. Salazar Park in East Los Angeles, where social-distancing guidelines were being enforced indoors. Only members of the same household were allowed to sit near each other inside the facility.
Among the visitors was East L.A. resident Miguel Diaz, who said he was aware that temperatures were forecast to exceed 100 degrees in the area. "So I just pretty much try to stay hydrated, drink as much water as you can," he said.
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"These highs on Saturday and Sunday will be about 15-25 degrees above normal across the region,'' the Weather Service said in a statement. "Temps will become dangerously hot for most areas, even over the coastal plain away from the beaches Saturday and Sunday. This kind of heat can be life-threatening and people are urged to use common sense, keep hydrated and stay out of the heat and in air-conditioned locations as much as possible.''
The anticipated high temperatures are sparking concerns about demand on the state's power grid as residents turn up their air conditioners.
The California Independent System Operator, which manages the power grid, announced that a Flex Alert -- a call for voluntary conservation -- will be in effect from 3 to 9 p.m. Saturday through Monday. Urging voluntary conservation is an effort to stave off too much strain on the state's electrical system, possibly leading to rolling power outages, like those that occurred during high heat last month.
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An excessive heat warning will be in effect until 8 p.m. Monday in the San Gabriel and Santa Monica mountains, Santa Catalina Island and the San Fernando, Santa Clarita, San Gabriel and Antelope valleys.
In Orange County, the warning will be in force in coastal areas from 10 a.m. Saturday until 8 p.m. Monday.