Two quakes rattle Southern California during historic heat wave

The sun shines over the financial district towers of downtown Los Angeles during a heatwave Friday, Sept. 6, 2024, in Southern California. Already dealing with a long and dangerous heat wave, SoCal residents also felt a little shaking Saturday as back-to-back earthquakes occurred near Ontario, Calif., about 40 miles from downtown LA. (AP Photo/Etienne Laurent)

LOS ANGELES – Southern California residents already dealing with a long and dangerous heat wave felt a little shaking Saturday, as two minor earthquakes occurred near Ontario, Calif.

A magnitude-3.9 earthquake struck at 10:34 a.m., centered about 4.4 miles southeast of Ontario and 4.7 miles northwest of Jurupa Valley in Riverside County, according to the US Geological Survey.

It was preceded by a magnitude-3.5 quake at 10:05 a.m. that was centered 4.3 miles southeast of Ontario, according to the USGS.

A magnitude-3.9 earthquake struck at 10:34 a.m., centered about 4.4 miles southeast of Ontario, Calif.

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Meanwhile, Southern California continued to bake under a historic heat wave Saturday, with three more days of triple-digit temperatures on the horizon before relief arrives Tuesday.

Excessive heat warnings were in effect through 8 p.m. Monday in much of the greater Los Angeles area for “dangerously hot conditions,” National Weather Service forecasters said. One warning took effect Tuesday morning in the western San Fernando Valley, and was extended three days longer than originally anticipated.

Power outages

Excessive heat was causing dozens of power outages throughout the Southland this weekend, affecting thousands of customers, according to utility officials.

“It will take time for crews to respond to and restore all affected areas as safely as possible, the LADWP posted at 4:45 p.m. “Please be patient with us as our crews continue to work around the clock.”

Friday’s high in downtown Los Angeles reached 112 degrees. It was the third time since July 1, 1877 that a high of 112 or more has been reached there, and just missed the record of 113 degrees set on Sept. 27, 2010.

Heat records were set or tied Friday at the following locations:

— LAX, where the high of 102 degrees broke the old record of 99 set in 2020;
— Long Beach Airport, where the high of 109 broke the record of 104 set in 2020;
— Hollywood/Burbank Airport, where the high of 114 tied the record set in 2020;
— UCLA, where the high of 105 tied the record set in 2020.

Woodland Hills reached 117 degrees on Friday, and Chatsworth reached 116. The Santa Ana Mountains and foothills and Orange County inland areas were also under excessive heat warnings until 8 p.m. Monday, with temperatures up to 105 degrees expected.

Even coastal areas are not immune from the heat. An excessive heat warning is in effect until 8 p.m. Monday for the Malibu coast and Los Angeles County beaches, along with the Palos Verdes Hills, with some of those areas possibly reaching 96 degrees, according to the NWS.

A less severe heat advisory will be in place for Orange County coastal areas until 8 p.m. Monday. Temperatures there are anticipated as high as 95 degrees.

The western San Fernando Valley was feeling some of the hottest weather, with Woodland Hills reaching 115 degrees Saturday and expected to reach 115 Sunday and 112 Monday.

Van Nuys saw a high of 112 on Saturday and was expected to drop to 107 the following two days, according to the NWS.

Pasadena was expected to hover around 104-105 degrees Saturday through Monday, while Lancaster was expected to range between 102 and 104 degrees.

Downtown Los Angeles was expected to hover around 102 degrees Saturday through Monday.

In Orange County, Anaheim was expected to reach 102 degrees both weekend days and 99 on Monday.

The nighttime was providing little relief, with overnight lows remaining in the upper 70s and lower 80s in many inland areas.

Forecasters and health officials repeated their warnings that this kind of heat can be life-threatening, and urged people to avoid outdoor activity.

“Our partners and us cannot emphasize this enough. Please refrain from hiking during excessive heat! Due to the marine layer, temperatures warm as you go up in elevation,” the NWS said.

The public was also reminded to never leave children and pets unattended in vehicles for even a minute, as they can quickly reach lethal temperatures.

The NWS also reminded people to keep their pets’ health in mind during the heat wave.

“Taking action to protect your pets from excessive heat is critical!” the agency posted on X. “Provide them with shade (or keep inside) and cool water, keep them off hot pavement and limit outdoor exercise. Hiking in the heat can kill your dog! Use extra caution!”

The excessive heat has also caused power outages throughout Los Angeles County, affecting thousands of customers.

Los Angeles Department of Water and Power customers can check the locations and status of outages at ladwp.com/outages. Southern California Edison customers can get updates at sce.com/outage-center/check-outage-status.

Los Angeles officials reminded residents that the city has hundreds of free locations open for relief from the heat including Recreation and Parks facilities and local library branches.

Locations and hours can be found at laparks.org/reccenter and lapl.org/branches.

The city also opened augmented cooling centers through Monday at the following locations:

— Fred Roberts Recreation Center, 4700 Honduras St.;
— Mid Valley Senior Center, 8801 Kester Ave., Panorama City;
— Sunland Senior Center, 8640 Fenwick St.;
— Jim Gilliam Recreation Center, 4000 S. La Brea Ave.;
— Lincoln Heights Senior Center, 2323 Workman St.;
— Lafayette Recreation Center, 625 S. Lafayette Park Place.

“LADWP has elevated its alert and increased crews to bring power back to those impacted by recent outages,” Mayor Karen Bass said in a statement issued Saturday. “A citywide coordination to protect Angelenos is in effect, and we will continue to urgently provide resources for Angelenos throughout Los Angeles in order to beat the heat.”

The hot, dry weather was also creating elevated fire conditions across the mountains, valleys and deserts throughout the week.

The NWS issued a red flag warning of heightened fire danger for the Santa Monica Mountains Recreational Area, San Gabriel Mountains, Western Antelope Valley Foothills and the 5 and 14 Freeway corridors until 10 p.m. Saturday.

Forecasters said wind conditions will “limit the potential for classic red flag criteria,” however, “there is a history of large fires with similar weather conditions during this time of the year.”

The NWS said humidity levels could drop to between 8 percent and 15 percent in the red flag areas, with little recovery during overnight hours.

Due to the high heat and heightened fire risk, Malibu’s Trancas Canyon Park and Charmlee Wilderness Park will be closed through at least Saturday, according to the city.

The continued extreme heat also prompted organizers of two outdoor events scheduled for Sunday to makes changes.

Sunday’s Santa Monica Classic running race – originally scheduled to consist of 5K and 10K runs – has been scaled back to a 5K only, with the start time moved up a half-hour to 7 a.m., enabling runners to start and finish before the hottest parts of the day, organizers said Saturday.

Similarly, the City of Hope cancer research center’s Walk for Hope in Duarte – originally set to hold 2K and 5K events – has been adjusted to a 2K only, while keeping its 9:30 a.m. start.

The region will see considerable relief once the heat wave breaks Tuesday, with temperatures expected to drop at least 10-12 degrees from Monday.

The rest of the week and next weekend will stay mild, with valley highs in the 80s and even upper 70s, and overnight lows dropping to the upper 50s and lower 60s. (CNS)