Thousands of firefighters battling a wildfire in Northern California received some help from the weather Saturday hours after it exploded in size, scorching an area greater than the size of Los Angeles. The blaze was one of several tearing through the western United States and Canada, fueled by wind and heat.

Cooler temperatures and an increase in humidity could help slow the Park Fire, the largest this year in California. Its intensity and dramatic spread led fire officials to make unwelcome comparisons to the monstrous Camp Fire, which burned out of control in nearby Paradise in 2018, killing 85 people and torching 11,000 homes.

Paradise again was near the danger zone. The entire town was under an evacuation warning, one of several communities in Butte County. Evacuation orders were also issued in Plumas, Tehama and Shasta counties. An evacuation warning calls for people to prepare to evacuate and await instructions, while an evacuation order means to leave immediately.

Temperatures are expected to be cooler than average through the middle of next week, but “that doesn’t mean that fires that are existing will go away,” said Marc Chenard, a meteorologist at the National Weather Service Weather Prediction Center in College Park, Maryland.

The Park Fire has scorched 547 square miles (1,416 square kilometers) as of Saturday and destroyed 134 structures since igniting Wednesday when authorities said a man pushed a burning car into a gully in Chico and then fled. It was 10% contained and moving to the north and east of Chico.

Ronnie Dean Stout, 42, was arrested Thursday at his home in Chico and was being held without bail pending a Monday arraignment, officials said. There was no reply to an email to the district attorney asking whether he had legal representation or someone who could comment on his behalf.

Billy See, an incident commander with the California Department of Forestry and Fire Protection, or Cal Fire, said at a briefing that the blaze had been advancing 8 square miles (21 square kilometers) per hour since its inception. But there was cautious optimism as weather conditions slowed it in some areas, and firefighters were able to plan and deploy additional personnel. Nearly 2,500 firefighters were battling the blaze, aided by 16 helicopters and numerous air tankers.

Jeremy Pierce, a Cal Fire operations section chief, said firefighters were taking advantage of the cooler weather: “We’re having great success today. Our crews are strong and going out there and getting this while the weather is in our favor.”

President Joe Biden was briefed on the Park Fire and directed his team to do everything possible to support suppression efforts, according to the White House.

In Southern California, a blaze in the Sequoia National Forest swept through the community of Havilah after burning more than 48 square miles (124 square kilometers) in less than three days. The town of 250 people had been under an evacuation order.

Benjamin Cossel, a fire information officer with the U.S. Forest Service, said firefighters and the sheriff’s office planned to go through the area to assess the damage and try to determine if any lives were lost.

“It’s still pretty hot in that area,” Cossel said.

Overall, more than 110 active fires covering 2,800 square miles (7,250 square kilometers) were burning in the U.S. as of Friday, according to the National Interagency Fire Center. Some were caused by the weather, with climate change increasing the frequency of lightning strikes as the region endures record heat and bone-dry conditions.

Susan Singleton and her husband packed their SUV with clothes, some food and their seven dogs and rushed to evacuate their home Wednesday in Cohasset, a town of about 400 northeast of Chico. She said they have since learned that their house burned down.

“Everything else we had burned up but getting them out, getting us out, was my priority,” Singleton said Saturday, standing outside her SUV where her dogs were resting. The couple and their pets have been sleeping in their car outside the Red Cross shelter at the Neighborhood Church of Chico, which does not allow pets inside.

Singleton, 59, said her priority was finding a place for her pets to stretch out.

“We’ve got to have a place to land and stop doing this because this is what’s stressing me out,” she said pointing to her little dogs inside small carriers.

Elsewhere, crews were making progress on another complex of fires in the Plumas National Forest near the California-Nevada line, Forest Service spokesperson Adrienne Freeman said. Traffic was backed up for miles near the border along the main highway linking Los Angeles and Las Vegas, as crews continued to battle a fire that started Friday when a truck crashed.

The most damage so far has been to the Canadian Rockies’ Jasper National Park, where 25,000 people were forced to flee and the park’s namesake, a World Heritage site, was devastated, with 358 of the town’s 1,113 structures destroyed. Authorities said cool and wet weather was helping, however.

In eastern Washington late Friday, crews stopped the progress of a fire near Tyler that destroyed three homes and five outbuildings, the Washington Department of Natural Resources said Saturday. The South Columbia Basin fire burned timber and grasses, and crews continued work on containment lines along the perimeter.

Two fires in eastern Oregon, the Durkee and Cow Valley blazes, burned about 660 square miles (1,709 square kilometers). Gov. Tina Kotek expressed condolences Friday to the family of a pilot of a single-engine air tanker that went down in forested terrain while fighting a separate fire near the town of Seneca and the Malheur National Forest.

In Idaho, homes, outbuildings and a commercial building were among structures lost in several communities including Juliaetta, which was evacuated Thursday. Officials said Saturday that they were continuing to assess the damage from a grouping of blazes referred to as the Gwen fire, which was estimated at 41 square miles (106 square kilometers) in size with no containment.

(AP)