A heat advisory signaling "a dangerous situation in which heat illnesses are possible" remains in effect today in several parts of LA County, including the San Fernando and Santa Clarita valleys and the San Gabriel and Santa Monica mountains.
The advisory will be in effect until 7 p.m. Saturday, the National Weather Service said.
"Very high temperatures will create a dangerous situation in which heat illnesses are possible," according to an NWS statement.
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The NWS warned that temperatures inside vehicles parked in hot weather "can quickly rise to life-threatening levels" even with windows left open, meaning people and pets must not be left in such vehicles.
The NWS also urged area residents to "drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors" since a "heat advisory means that a period of hot temperatures is expected which will create a situation in which heat illnesses are possible."
No heat advisory was issued for the San Gabriel Valley because sea breezes are expected to filter into that region, keeping temperatures below inordinately hot levels, said Oxnard-based NWS meteorologist Curt Kaplan.
Heat advisories are not issued for the Antelope Valley, where it's always warm at this time of the year; the NWS only warns of "excessive heat" in the Antelope Valley, Kaplan said. As for L.A. proper, it gets a heat advisory when highs reach the mid 90s, not low 90s, as is the case today, he said.
The San Fernando Valley will be about nine degrees above normal today, Kaplan said, adding that a "nice cool-off" is expected early next week, once the high pressure now over the Southland dissipates. In fact, temperatures in some LA County communities will be below normal next week, Kaplan said.
Today's temperatures will be about the same as Friday, ranging from the mid-80s inland to the low triple digits in the Valleys, but decline a few degrees Sunday and several more Monday.
Sunny skies were also forecast in Orange County, along with highs in the 80s and 90s. Temperatures will decline by several degrees on Sunday.