Southern California heat wave timeline: When extreme temperatures, red flag warnings peak

Published August 26, 2026 7:09 AM PDT

Southern California is experiencing a prolonged heat wave that brings dangerously high temperatures and an elevated risk of wildfires to the region through the end of the week.

What we know:

Extreme heat warnings remain in effect for much of the region through 8 p.m. Friday, according to the National Weather Service.

Temperatures across inland areas, valleys, and mountain ranges are projected to climb 10 to 15 degrees above average, topping out as high as 112 degrees. 

Even coastal regions face temperatures in the 90s to low 100s, with Orange County coastal zones remaining under a heat advisory while inland areas face extreme heat warnings.

A red flag warning indicating critical fire danger is active until 3 p.m. Friday for the San Gabriel Mountains and the 5 and 14 freeway corridors in northern Los Angeles County. 

High temperatures in these red flag areas could reach 108 degrees, with humidity levels dropping below 10% and wind gusts up to 30 mph.

To prepare for emergencies, the Los Angeles County Fire Department has pre-positioned personnel and equipment. 

Possible power shutoffs

Southern California Edison warned that roughly 3,100 customers in Los Angeles County, including areas near Malibu, Castaic, and the Santa Monica Mountains, could face precautionary Public Safety Power Shutoffs to prevent electrical equipment from igniting fires.

City and county officials have opened designated cooling centers, splash pads, and public pools to help residents manage the extreme weather. 

The public is advised to stay hydrated, limit outdoor activities during peak sun hours, and monitor high-risk individuals.

Record high temps

By the numbers:

Here is a breakdown from the NWS of historic record highs for Tuesday, along with Wednesday's forecasted high temperatures:

Downtown LA 

Record high temp: 98 in 1981

Forecasted high temp: 101 

LAX

Record high temp: 94 in 1985

Forecasted high temp: 86 

Long Beach 

Record high temp: 100 in 1981

Forecasted high temp: 99

Hawthorne

Record high temp: 88 in 2015

Forecasted high temp: 93 

Santa Monica

Record high temp: 85 in 2011

Forecasted high temp: 87

Burbank 

Record high temp: 111 in 1944

Forecasted high temp: 105

Van Nuys

Record high temp: 105 in 2010

Forecasted high temp: 107

Woodland Hills

Record high temp: 109 in 1981

Forecasted high temp: 111

Palmdale 

Record high temp: 107 in 2011

Forecasted high temp: 105

Lancaster

Record high temp: 106 in 1950

Forecasted high temp: 105

Camarillo

Record high temp: 86 in 2015

Forecasted high temp: 105

Oxnard

Record high temp: 86 in 2015

Forecasted high temp: 90

Santa Barbara

Record high temp: 86 in 1977

Forecasted high temp: 85

Santa Maria 

Record high temp: 92 in 1925

Forecasted high temp: 86

Paso Robles

Record high temp: 106 in 2017

Forecasted high temp: 107

What we don't know:

It's unclear whether Southern California Edison will need to execute the potential power shutoffs for the 3,100 targeted customers, as decisions will depend on real-time wind and humidity conditions. 

Timeline:

Peak temperatures are expected on Wednesday and Thursday before leveling off slightly on Friday. 

The red flag fire danger warning expires at 3 p.m. Friday, followed by the expiration of the extreme heat warnings at 8 p.m. Friday. 

Temperatures are forecasted to drop significantly by next week.

What they're saying:

"High and low temperatures will continue to rise through Thursday, to as much as 10 to 15 degrees above average, with not much change for Friday," according to the NWS.

What's next:

Weather patterns indicate that relief from the excessive heat will arrive early next week as temperatures drop across the region. 

In the meantime, local agencies will maintain heightened staffing levels to respond to potential brush fires and heat-related health emergencies.

What you can do:

Residents are encouraged to spend time in air-conditioned spaces, maintain high fluid intake, and avoid direct exposure to the sun during peak hours. 

Beachgoers should exercise caution due to elevated surf conditions and strong rip currents.

The Source: This report is based on information provided by the National Weather Service, the Los Angeles County Fire Department, local health officials, and Southern California Edison.

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