• Temperatures are forecast to be in the triple-digits for most of California during the holiday weekend
  • The National Weather Service advised residents to stay in cool spaces and avoid strenous activity as much as possible
  • There is fear the heatwave could help strengthen the wildfires burning across California after crews were able to make siginificant headway against them

The National Weather Service warned Californians on Thursday to prepare for a blistering heatwave that will grip most of the state during Labor Day weekend.

The forecast also has sparked concern that the various wildfires across northern California could intensify after fresh crews and cooler weather helped make headway in containing the blazes.

“Friday will kick off the well-advertised, dangerous and long-lived heat wave,” the NWS said in a press release. “Max temps will jump 4 to 8 degrees away from the coasts. Max temps will be 4 to 8 degrees above normal for the interior coastal sections and valleys and about 12 degrees above normal for the interior. Excessive heat warnings will go into effect at 10 am for all non-coastal areas.”

Residents of Los Angeles and Ventura counties were warned they may be in for the worst of the heatwave as average temperatures are expected to be between 110 and 115 degrees. Sunday is forecast to be the heatwaves peak, with the NWS saying temperatures may be “hazardous” in some areas.

“Most areas will see another 2 to 4 degrees of warming with the very notable exception of the Central Coast where a bigger offshore push is forecast which will result in 5 to 10 additional degrees of warming,” the NWS said.

Residents are urged to stay inside or in cooled areas and avoid strenuous activity as much as possible during Labor Day weekend due to potential health risks. They were also warned to be ready for potential power outages as the heatwave is expected to cause additional strain on the power grids.

The heatwave is forecast to begin dissipating on Monday as cooler temperatures begin rolling across most of the California coast. It will continue cooling as the week goes on, but the heat is expected to linger in some of the state’s valley and desert regions.

However, arguably the biggest concern is how the weekend heatwave may impact the wildfires still raging across the state.

The last week has seen the crews make significant progress against the fires, especially against the two largest fires in northern California. The California Department of Forestry and Fire Protection said crews have contained over 75% of the fires and have nearly contained most of the smaller fires with only a couple of exceptions.

Despite these gains, there is concern the weekend heatwave and the drier weather alongside it could help reinvigorate the fires.

As of Thursday, the SCU Lightning Complex fire was the biggest wildfire still going with over 391,000 acres burned. It has been the least destructive of the three biggest wildfires, destroying or damaging 122 structures and leaving five people injured. Cal Fire said crews have contained 78% of the fire.

Next is the LNU Lightning Complex fire which burnt through over 375,000 acres while crews contained 81% of the blaze. The LNU fire has been the most destructive of the three biggest fires as it has destroyed or damaged 1,722 structures, injured four people, and killed five people.

The CZU Lightning Complex fire remains the smallest of the three biggest fires with over 85,000 acres burned. It’s also been one of the hardest for crews to fight as only 48% of the fire has been contained. It has damaged or destroyed 1,630 structures, injured one, and killed one.

A new scorching temperature of  130 degrees Fahrenheit (54.4 degrees Celsius) recorded in California's Death Valley could be the highest ever recorded, US officials say
A new scorching temperature of 130 degrees Fahrenheit (54.4 degrees Celsius) recorded in California's Death Valley could be the highest ever recorded, US officials say GETTY IMAGES NORTH AMERICA / DAVID MCNEW