Wildfires across West US put millions under air quality alerts amid 'explosive growth' of blazes

A pall of smoke from wildfires blazing across the western United States and Canada has triggered air quality alerts for millions, as legions of firefighters confront the infernos, including California's biggest wildfire this year.

Dubbed the Park Fire, the conflagration had engulfed an expanse surpassing Los Angeles in size by Sunday, casting a dark shadow of smoke across the sky and deteriorating air conditions over a vast region of the northwestern US and western Canada. The fire's footprint stretched over more than 562 square miles (1,455 square kilometers) in inland Northern California.

On Saturday, cooler temperatures and increased humidity lent a hand to firefighters, allowing them to achieve some headway, boosting containment from zero to 12%. Memories of the devastating 2018 Camp Fire that ravaged the neighboring town of Paradise, claiming 85 lives and destroying 11,000 homes, have been evoked by the blaze.

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Evacuation warnings were in place for Paradise and other communities in Butte County on Sunday. Yet, Cal Fire operations section chief Jeremy Pierce delivered a glimmer of hope midday, announcing that the Park Fire's southern edge, nearest to Paradise, was "looking really good," with efforts concentrated on stamping out lingering hot spots and clearing hazards in the following three days.

He also reassured that there was no expectation for the fire to advance toward Chico, a city home to roughly 100,000 residents situated west of Paradise. Initially, first responders were focused on saving lives and property from the Park Fire, but now they're directly tackling the blaze, according to Jay Tracy, a spokesperson at the Park Fire headquarters.

Almost 4,000 firefighters are currently battling the fire, supported by numerous helicopters and air tankers. Tracy mentioned that additional reinforcements would provide much-needed rest for local firefighters, some of whom have been working tirelessly since the fire began on Wednesday.

"This fire is surprising a lot of people with its explosive growth," he stated. "It is kind of unparalleled." In areas where the flames had subsided by Sunday, the destruction was evident. Mailboxes and vehicles in Cohasset were coated with pink fire retardant dropped from aircraft.

In other parts of the community, remnants of a washer and dryer set were surrounded by charred debris from a house, and a burnt motorcycle remained upright, balanced on rims after its tires seemingly melted away. However, another part of the town remained relatively untouched, according to the Butte County Fire Chief.

"We have an unburned island in that community that we are continuing to patrol and ensure that there are no hot spots in it," Sjolund said. Managing evacuation orders can be complex. Butte County Sheriff Kory Honea revealed that authorities were about to downgrade the evacuation order to a warning for Forest Ranch when they discovered several hot spots reported nearby.

"That illustrates how rapidly things can change - we were all set to be able to reduce that order to get people back in there," Honea said. In Southern California, about 2,000 residents have been told to evacuate due to a wildfire tearing through the Sequoia National Forest.

The blaze, propelled by strong winds, has devoured over 60 square miles (155.4 square kilometers) within just four days, according to Kern County Fire Department spokesperson Andrew Freeborn. The National Weather Service has issued a "red flag" warning for the area, signaling that dry conditions and gusty winds are heightening the risk of fire.

Exhibiting extreme behavior, the fire is being fueled by an abundance of dead vegetation parched after years without significant rain, Freeborn explained. The old mining town of Havilah and other nearby communities have been "heavily impacted" by the flames, he noted, although it's too early for damage assessment teams to determine the extent of destruction to homes.

Thankfully, no deaths have been reported in connection with the Park and Borel fires. Despite evacuation orders, some locals are opting to stay put, a choice that Freeborn warns increases risks for everyone involved.

"When people are trying to ignore the orders and later call for rescue, that takes firefighters away from the task of fighting the fires," he warned. "This fire is moving at a pace and with such intensity that individuals should not be thinking they can wait until the last minute. They need to get out of the way."

Despite cooler-than-average temperatures predicted for the middle of this week, it does not necessarily mean "that fires that are existing will go away," articulated Marc Chenard, a meteorologist at the National Weather Service's Weather Prediction Center in College Park, Maryland.

Damage caused by the Park Fire includes at least 66 ruined structures and five others damaged, according to Tracy. Initially, based on drone footage, authorities believed that 134 structures had been destroyed; however, after an in-person evaluation, the number was revised.

"Unfortunately, that number will probably go up," Tracy confessed. "Each day that number has potential to grow - our teams obviously don't do damage inspections when there is active fire in an area." Jerry White, aged 72, evacuated his Magalia home following an official warning, one step below a full-scale evacuation order.

Having suffered severe third-degree burns years prior due to a barbecue mishap setting his coat alight, White admitted the memory of the pain spurred him to take the warning seriously. "I don't want to catch fire again. It's one of the worst pains you can endure," disclosed White. "I wanted to get out of dodge. Burns are bad."

White's residence remains untouched by the inferno, and he's determined to stay in his mountain home despite the risks. "I've been up here 50 years," White declared. "The beach is more dangerous than here ... it was packed by sharks before, back when I used to surf. I'll take a fire over a shark any day!"

The Park Fire ignited on Wednesday, allegedly after a man set a car ablaze and rolled it into a ravine in Chico before escaping. The suspect was apprehended on Thursday and is scheduled for a court appearance on Monday.

As of Sunday, the Park Fire was just one among over 100 wildfires scorching the US as reported by the National Interagency Fire Center. Many were triggered by natural phenomena, with climate change amplifying the number of lightning strikes amidst the western US's scorching heat and arid conditions.

Even though fire conditions have improved in Northern California, the threat of new fires sparking remains high. The National Weather Service issued "red flag" warnings for Sunday, covering vast regions of Idaho, Montana, Utah, Colorado, and Wyoming, along with parts of California.

Fires are also raging across eastern Oregon and Idaho, where authorities are evaluating the aftermath of the Gwen Fire, which spanned an estimated 43 square miles (111 square kilometers) by Sunday.