California is facing a prolonged late-summer heat wave this week, with widespread triple-digit temperatures starting in the south and spreading northward, the National Weather Service said Monday.

Excessive heat watches will go into effect Wednesday morning and remain in effect through Sunday evening in a large swath of Southern California, including much of the normally temperate coastline, forecasters said.

Temperatures were predicted to top 100 degrees (37.7 Celsius) in many valley and mountain locations.

“This heat may be record breaking and will likely produce a very high heat illness risk,” the Los Angeles-area weather office wrote.

(TNS) - A late-summer heat wave in Southern California typically sends people fleeing to movie theaters, shopping malls and crowded beaches in search of a cool respite.

But the coronavirus pandemic has forced the closure of places where people once gathered, upending those routines.

So as temperatures soared Friday, many people instead stayed at home with their air conditioners blasting. Even though many offices and businesses were closed due to the pandemic, that intense demand — along with other factors including a dearth of power coming in from other states — was enough to create the most serious statewide energy shortage in nearly 20 years, officials said. On Saturday night, another round of temporary blackouts was ordered in parts of the state.

The current heatwave broiling Californians like no event in decades is also elevating the risk for another potential disaster in the weeks ahead: wildfires.

While heat and dry conditions have contributed to the Lake and Ranch fires burning now in Los Angeles County, fear of larger blazes looms in the weeks ahead. As a result of climate change, California sees more than twice as many fall days with “fire weather” as it did a generation ago. The current heatwave raises the odds of “wildfires later in 2020, that’s for sure,” says Daniel Swain, a climate scientist at UCLA and the National Center for Atmospheric Research.

A second day of unrelenting heat is scorching California, sending temperatures to near record levels, raising risk of wildfires and prompting calls for energy conservation.

Temperatures surged past 100 degrees Fahrenheit in parts of Northern California Tuesday, with heat advisories in effect across the state. Sacramento was forecast to hit 103 degrees.

In the wake of hurricanes Florence and Michael and myriad other devastating storms and wildfires stacking up during the last decade, an updated assessment of California’s changing climate offers the projection of more of the same.

The assessment said Californians can expect more heat and more extreme weather, which would lead to more wildfires, floods, drought and public health issues. California’s Fourth Climate Change Assessment was produced as part of a volunteer initiative by climate experts. The assessment updates the third one issued in 2012.