A dangerous heat wave will intensify across the Southland Friday, pushing temperatures into the triple digits in many inland communities through the weekend.
Widespread moderate to high heat risk is expected through Sunday as a strengthening high-pressure system drives temperatures well above seasonal averages, according to the National Weather Service.
“Temperatures will become dangerously hot in many areas Friday through the upcoming weekend as the next heat wave arrives,” the NWS said.
Valley and inland areas are expected to see highs well over 100 degrees Friday and Saturday, while intermediate areas between the coast and valleys, including downtown Los Angeles, are forecast to reach the upper 80s to mid-90s.
Forecast highs are within a degree or two of daily records in many locations, with Saturday offering the greatest chance of setting new records, according to the weather service.
Areas such as Acton, Lancaster and Palmdale all topped 100 degrees Thursday, while many valley areas such as Van Nuys and Burbank were in the 90s. Downtown Los Angeles was in the upper-80s late Thursday afternoon.
“In addition to the traditional daytime heat threat, overnight lows will remain well above normal in response to the very warm ocean temperatures, so there won’t be as much relief at night as we are accustomed to,” the NWS said.
An extreme heat warning will be in effect through 8 p.m. Sunday for the Antelope Valley and Antelope Valley Foothills, where temperatures of 104 to 114 degrees are possible.
In the western San Gabriel Mountains and the 5 and 14 Freeway corridors, a heat advisory will be replaced by a more severe extreme heat warning at 10 a.m. Friday through 8 p.m. Sunday, when highs are expected to range between 95 and 105 degrees.
An extreme heat warning will also be in effect from 10 a.m. Friday through 8 p.m. Sunday for the Santa Monica Mountains Recreational Area, Calabasas, Agoura Hills, the San Fernando and San Gabriel valleys and the Los Angeles inland coastal area, including downtown. Those areas could see “dangerously hot conditions” with temperatures of 95 to 110 degrees, according to the NWS.
The eastern San Gabriel Mountains will be under a heat advisory through 8 p.m. Sunday, while Los Angeles County beaches, the Malibu coast and Palos Verdes Hills will be under a heat advisory from 10 a.m. Friday through 8 p.m. Sunday. All of those areas could see temperatures as high as 100 degrees, forecasters said.
In Orange County, the hottest conditions are expected Saturday, with Anaheim forecast to reach 92 degrees Friday and 95 Saturday.
An extreme heat warning will be in effect from 10 a.m. Friday through 8 p.m. Sunday in the Santa Ana Mountains and foothills, and in Orange County inland areas, which could see temperatures in the upper 90s. A less severe heat advisory will be in effect for Orange County coastal areas from 10 a.m. Friday through 8 p.m. Sunday, with highs expected in the mid-80s to lower 90s.
The weather service also warned that the combination of extreme heat, dry fuels, and locally gusty winds could increase the risk of large wildfires heading into the weekend.
Although a gradual cooling trend is expected to begin Sunday, forecasters said temperatures will remain above normal into next week as high pressure continues to dominate the weather pattern, with heat hazards potentially lingering for several more days.