Triple-digit temperatures have prompted an excessive heat warning and a statewide advisory to conserve energy as residents crank up their air conditioners to counter the late-summer swelter.
Officials have issued a statewide "Flex Alert" in effect Friday through Sunday, urging residents and businesses to conserve electricity, raise the air conditioner to 78 degrees, and postpone use of major appliances until 6 p.m.
Forecasters predict at least two more days of triple-digit temperatures in the deserts and valleys across Southern California before cooling down on Sunday.
Valley areas could see weather records broken on Friday.
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Areas where temperatures are expected to top triple digits are Pasadena -- 101 on Thursday and 103 on Friday; Woodland Hills -- 108 on Thursday and 109 on Friday.
Other areas that could see triple-digits on Thursday and Friday are Burbank -- 101 and 102; Palmdale -- 106 and 108; Riverside -- 107 for both days.
Coastal areas, meanwhile, could be some 30 degrees cooler. The high in Malibu is expected to hit 70 on Thursday.
The weather is caused by a big upper-level, high pressure system moving in over the area, said Scott Sukup, a meteorologist with the National Weather Service.
“It’s really squishing the marine layer down,” he said. “It’s unusual in that we’re getting close to record highs. This is the time of the year when you see these heat waves.”
Heat records were broken this week.
Woodland Hills, typically the hottest part of the San Fernando Valley, broke a record on Wednesday with a high of 107 degrees. The old record was 106, set in 1982.
Several areas tied heat records.
On Tuesday Sandberg tied its record of 96 degrees set in 1995. Lancaster tied its record on Tuesday of 107, set in 1978. Woodland Hills tied its record on Monday of 108, set in 1997.
The lack of rainfall and extreme heat has prompted fire agencies to be on alert for brush fires. There hasn’t been any significant rain since April. Through July, most areas have received about half of their annual rainfall.
The National Weather Service issued an excessive heat warning for greater Los Angeles through 8 p.m. Friday. The advisory urges residents to stay hydrated and out of the sun.
“People do take the necessary precautions,” said Los Angeles Fire Department spokesman Matt Spence. “But you do sometimes still see isolated incidents.”
Spence said the fire department has seen no significant uptick in calls for service due to the heat.
“But today may be different story,” he said.
The extreme conditions have prompted the fire department to add staff to stations in hillside areas such as Tujunga, the Hollywood Hills and Santa Monica Mountains, Spence said.
“There’s definitely concern for those areas and we’re always on alert,” Spence said.
Los Angeles Department of Water and Power urged people to conserve energy as power use is expected to approach an all-time high.