Extreme heat broils Southern California -- even overnight

Broiling conditions continued Thursday across Southern California, with triple-digit temperatures forecast from the San Fernando Valley to Orange County and the Inland Empire.

The National Weather Service said muggy, hot conditions about 10 degrees above normal. Officials warned overnight temperatures could stay above 80 degrees.

Los Angeles County public health officials issued a heat alert for Thursday and Friday as the region braces for another day of temperatures that in some places could hit 20 degrees above normal. The NWS issued a heat alert for Orange County and the Inland Empire.

Triple-digit temperatures are expected in the western San Fernando Valley, Santa Clarita Valley and Ventura County, and other areas will feel as if it is in the 100s when the humidity is factored in, according to the National Weather Service.

In his warning issued Wednesday, county Public Health Director Jonathan Fielding said it was “critically important” to never leave children, older adults or pets unattended in homes with no air conditioning.

People and pets who are susceptible to heat are particularly vulnerable in vehicles, even with the windows cracked open or down, Fielding warned, because temperatures inside “can quickly rise to life-threatening levels.”

Those looking to cool off this week can head to the coast, where the ocean breeze will keep the temperatures in the 70s, or to one of several cooling centers open throughout Los Angeles County.

The latest heat wave to hit Southern California is courtesy of large high-pressure system lingering over the Midwest. Until at least Friday, temperatures will be above normal for this time of year, with 80s at the beaches, 90s across the inner coastal areas and up to 105 degrees in the valleys, the National Weather Service said.

“And there will not be much overnight relief,” said weather service specialist Stuart Seto.

In some valley areas, the mercury isn’t expected to drop below 80 degrees overnight.

Not until Sunday will the Southland see any sort of relief from the heat, but even then, temperatures will remain above normal, with highs in the mid-80s at the beaches and 90s in valleys, according to the weather service.

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