About 560 wildfires burn in California as more than 100,000 people evacuate: Here's what we know

Amid a scorching heat wave that is now in its second week, hundreds of wildfires are burning in California, forcing over 100,000 people to evacuate.

Blazes threatened homes and blackened city skies Friday as firefighters pleaded for more help in their efforts to contain the fires, according to officials. At least six people have died.

The state is battling about two dozen large complex fires, Gov. Gavin Newsom said Friday. In total, 560 fires are raging in the state.

Major fires in Southern California are coming under control, and the state is shifting resources to battle massive blazes in Northern California, Newsom said. There, fires have chewed through brushland, rural areas, canyon country and dense forest surrounding San Francisco.

Newsom confirmed 5 deaths have associated with the fires. Separately, a Pacific Gas & Electric utility worker was found dead Wednesday in a vehicle in the Vacaville area.

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In the past week alone, fires have charred over 1,200 square miles across the state, according to Cal Fire — a size comparable to Rhode Island.

“We’re putting everything we have on this,” Newsom said, noting the state is seeking aid from the federal government, other states as far away as the East Coast and even Canada and Australia. California firefighters are "overwhelmed" by the ongoing fires, he said.

Two of the fires there are now the 7th and 10th largest fires in state history, having burned as much as 300 square miles each, Newsom said Friday.

“If you are in denial about climate change, come to California,” Gov. Gavin Newsom said, as he addressed the wildfires in a last-minute video recorded for the Democratic National Convention on Thursday night.

More than 12,000 firefighters are on the front lines, but fire officials in charge of each of the major fire complexes say they are strapped for resources. Some firefighters were working 72-hour shifts instead of the usual 24 hours.

Here's what we know:

6 dead, over 30 injured

The fires burning throughout Northern California have now claimed at least six lives and injured 33 people and firefighters.

On Friday, authorities reported three civilian deaths in Napa County and one death in Solano County.

In central California, a pilot on a water-dropping mission in western Fresno County died Wednesday morning when his helicopter crashed — a fatality confirmed by Newsom Friday.

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Additionally, a utility worker was found dead Wednesday in a vehicle.

At least two other people were missing and more than 30 civilians and firefighters have been injured, authorities have said.

More than 100,000 people have evacuated

Newsom pleaded with California residents to take evacuation orders seriously, saying 119,000 people have already evacuated their homes. More than 140,000 people are under evacuation orders.

Tens of thousands of homes have been threatened by flames as some fires have doubled in size within 24 hours, according to fire officials.

In Solano County, evacuation orders were given to thousands of residents — some fled for the first time ever.

“I’ve lived here for 30 years, never had to evacuate before,” resident Tim Lukehart said. “There’s been fires of course, but not like this one.”

While some evacuations were lifted in the town of Vacaville, between San Francisco and Sacramento, other areas increased the size of evacuations. The University of California, Santa Cruz was evacuated, and a new fire burning near Yosemite prompted residents to flee.

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How many fires are burning in California right now?

Of the 560 fires burning throughout the state, dozens of fires have collected into major complex fires.

Many were sparked by an unprecedented lightning siege of nearly 12,000 strikes over several days, as a high-pressure area over the West brought a dangerous mix of triple-digit heat and monsoonal moisture pulled from the south.

The largest fire listed on Cal Fire's website Friday evening was a blaze made up of 20 separate fires burning near San Jose, which has been named the SCU Lightning Complex Fire. The fire had ravaged more than 359 square miles and is 10% contained.

Another large fire burning in California is the LNU Lightning Complex, which has burned a total of 342 square miles and is 7% contained.

What is the air quality and why don't cloth face masks help?

Smoke from the fires is making the air quality in parts of California some of the worst in the world. And people in the area might not be able to smell the dangerous pollutants in the air.

Air quality experts measure the amount of fine particulate matter (PM 2.5) in the air. According to the U.S. Environmental Protection Agency, those particles come from a variety of sources, including fires.

Smoke from fires can send large amounts of PM 2.5 into the air and over large areas.

“Whenever things burn there’s a mixture of gases and particles,” said University of California, San Francisco pulmonologist Dr. John Balmes, an expert on the respiratory and cardiovascular effects of air pollutants.

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“When you smell smoke, you are smelling the gases in the air, not PM 2.5,” Balmes said. “They go hand-in-hand near the fire source, but the particulates travel in the upper atmosphere.”

It’s possible to have bad air — air high in PM 2.5 — without smelling gases.

Your coronavirus mask may not protect you, unless you have a mask designed to filter PM 2.5, like an N95. Those masks are scarce worldwide because of the pandemic.

Health experts say limiting outdoor activities, remaining indoors with the windows and doors closed and turning on an air conditioner with a recirculation setting can help reduce your risk if you live in an affected area.

Contributing: Jessica Skropanic, Redding Record Searchlight; The Associated Press, Doyle Rice, Elinor Aspegren, USA TODAY

This article originally appeared on USA TODAY: California fires: About 560 wildfires burning right now 6 dead