San Diego Unified Schools plan to let many students out early Friday as temperatures soar from a heat wave expected to last through the Labor Day weekend.
California could see a new all-time record demand on its power grid, according to the California Independent System Operator.
The agency that manages most of the state's power grid, announced a Flex Alert for Friday. Cal ISO asked Californians for voluntary power reductions from 1 to 10 p.m. when air conditioning use is at its peak.
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Temperatures throughout San Diego County were expected to range from 97 to 107 degrees.
Excessive heat warnings were in effect for Orange, Riverside and San Diego counties according to the National Weather Service.
The heat is not just in Southern California. In the Bay Area, triple-digit temperatures could set or match records. Livermore is expected to reach 115 degrees, a temperature last seen in 1950.