Los Angeles faces scorching 119° as heat wave affects 31 million in CA, Nevada and Arizona

Scorching, triple-digit temperatures across Southern California led to warnings from public health officials, power outages and some schools closing early Friday as part of a larger heat wave gripping an area of the southwestern U.S. spanning three states.

More than 31 million people in California, Nevada and Arizona were under an excessive heat warning issued by forecasters as temperatures soared Friday, according to the National Weather Service. In much of Southern California, the extreme weather is expected to last until Monday night after forecasters extended an earlier heat warning that was supposed to end Friday. 

Residents of the region faced grueling temperatures — from 119 degrees in Woodland Hills to 115 degrees in Riverside — as air quality regulators warned of unhealthy breathing conditions tied to the heat and some Los Angeles area schools ended classes early due to the weather and power outages. 

In Pasadena, rolling outages were issued after the heat caused an equipment failure. Later Friday evening, more than 16,500 households faced outages in the city of LA alone as Mayor Karen Bass told residents that LA Department of Water and Power crews were working to restore the power "quickly and safely."

And a number of cities saw record-breaking temperatures throughout the day.

The excessive heat warning extends from the southernmost end of Central California all the way across Southern California to the U.S.-Mexico border. The National Weather Service has warned of "dangerously hot conditions." 

It will remain in effect until 8 p.m. Monday for much of Santa Barbara County and most areas south including parts of LA, Ventura, Orange, San Bernardino, Riverside and San Diego counties. 

Only San Luis Obispo County will see the advisory end earlier, with it set to expire Saturday at 8 p.m. there.

Other parts of California further north are under a less severe heat advisory that's also warning of warmer than usual weather.   

Forecasters have issued a red flag warning for mountain areas of LA, Ventura and Santa Barbara counties due to especially dry, hot conditions that can spark and quickly spread wildfires — telling people in high-risk areas to be ready to evacuate. In San Bernardino County, a wildfire grew to more than 1,100 acres after starting the day before and triggering evacuation warnings. 

On Friday, with the sweltering heat expected to continue into the weekend, public health officials in LA County spoke out.

"As temperatures are forecast to continue to soar into the triple digits, the Los Angeles County Department of Public Health urges residents to take precautions to avoid heat-related illnesses such as heat exhaustion, heat stroke and heat cramps," said Dr. Anish Mahajan, chief deputy director of the health department. 

People who are especially vulnerable include those with chronic health conditions, children, pregnant women, elderly people as well as athletes and workers who spend long stretches of time outside, he said.

"Workers who are working outside are at really high risk of heat-related illnesses," Mahajan said, explaining that employers are legally required to provide workers at outdoor job sites with shade when temperatures exceed 80 degrees.

In LA's Los Feliz neighborhood, as the temperature reached 103 degrees Thursday, firefighters spent nearly six hours rescuing a construction worker trapped inside an 8-foot deep trench, surrounded by soil reaching up to his shoulders. 

Two of the firefighters were treated for heat exhaustion, with one of them taken to a hospital, while the worker was left in serious condition and also had to be rushed to a hospital after being trapped underground in the baking heat for hours. 

Meanwhile, for the broader population, air quality has become a real point of concern.

Ozone pollution — specifically "ground-level ozone" which develops when gases from pollution interact with sunlight and form ozone smog — is currently at concerning levels across Orange, LA, San Bernardino and Riverside counties, according to the South Coast Air Quality Management District. The regulator issued an ozone advisory that will remain in effect until Monday at 8 p.m.

People are being told to stay indoors, avoid physical activity and conserve electricity due to the poor air quality. Health risks such as shortness of breath, wheezing and coughing are possible as well as more serious health effects over the long run, according to the American Lung Association. 

"Many areas in the United States produce enough ozone during the summer months to cause health problems that can be felt right away," the organization says. "Long-term ozone exposure is associated with increased respiratory illnesses, metabolic disorders, nervous system issues, reproductive issues... cancer and also increased cardiovascular mortality, which is the main driver of total mortality."