Firefighters battle numerous fires at the height of the heat wave in California

With record temperatures expected across the state and fires sparked by illegal fireworks, the risk of wildfires is increasing this weekend.

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CALIFORNIA – Firefighters battled a number of wildfires as a persistent heat wave combined with Fourth of July fireworks across the Golden State posed extreme fire danger.

Emergency crews made progress Friday in battling a California wildfire that prompted widespread evacuation orders, but damage assessments showed 25 buildings were destroyed and forecasters predicted heat and fire dangers were increasing on the West Coast.

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Containment on the Thompson Fire near the city of Oroville in Butte County increased from 29% to 46% overnight, according to the California Department of Forestry and Fire Protection. The fire had expanded only slightly overnight and was now just under 6 square miles in size.

A firefighting aircraft drops fire retardant to prevent the spread of the Grubbs Fire in the Palermo community of Butte County, Calif., Wednesday, July 3, 2024. Firefighters stopped the fire at about 10 acres. (AP Photo/Noah Berger)

Most evacuation orders for about 17,000 people were lifted on Thursday.

Firefighters “did a really good job yesterday” enforcing the exclusion lines, and the wind was not a factor, said Cal Fire Captain Alejandro Cholico, a fire department spokesman.

A new fire called the French Fire broke out Thursday evening, triggering evacuations in the small gold mining town of Mariposa in the foothills of the Sierra Nevada along a highway leading to Yosemite National Park.

Bulldozers and workers drew a line across the entire east side of Mariposa as flames spread across 1.3 square miles (3.4 square kilometers) before fire activity subsided.

“Winds have calmed, helping firefighters make progress overnight,” Cal Fire said in a report.

Firefighters walk down a hill with scorched ground behind them as they battle the French Fire in Mariposa, Calif., on Friday, July 5, 2024. (AP Photo/Noah Berger)
Flames from the French Fire engulf a storage area at a sports field in Mariposa, Calif., on Friday, July 5, 2024. (AP Photo/Noah Berger)

In addition to the buildings destroyed by the Thompson Fire, six others were damaged. There was no immediate information on the type of buildings, but several homes were ablaze when the fire broke out Tuesday morning about 70 miles (110 kilometers) north of Sacramento.

The number of reported firefighter injuries has dropped from four to two, Cholico said. The cause of the fire is still being investigated.

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The Oroville region is no stranger to disasters. The deadliest and most devastating wildfire in state history nearly wiped out the Butte County town of Paradise in 2018.

This week, firefighters managed to contain the Sharp Fire, which threatened several homes and a hospital in Simi Valley, Southern California. By Thursday afternoon, crews had contained the fire to 60 percent and limited it to 160 acres.

A plane drops flame retardant on a hillside during the Sharp Fire in Simi Valley, Calif., Wednesday, July 3, 2024. (AP Photo/Eric Thayer)
A helicopter drops water on a hillside during the Sharp Fire in Simi Valley, Calif., Wednesday, July 3, 2024. (AP Photo/Eric Thayer)

Also in Southern California, firefighters across the Inland Empire were battling several fires sparked by Fourth of July fireworks late Thursday, including a 17-acre fire in Perris and a nearly 60-acre fire in Moreno Valley.

Meanwhile, meteorologists warned that the devastating heat wave in California would continue and spread to the Pacific Northwest and neighboring western states.

“The duration of this heat is also concerning, as above-average temperatures are forecast to continue into next week,” the National Weather Service wrote.

Among the extremes, the forecast for Furnace Creek in Death Valley National Park calls for daytime highs of 129 degrees (53.89 degrees Celsius) on Sunday and then about 130 degrees (54.44 degrees Celsius) through Wednesday. The official world record for the highest temperature recorded on Earth was 134 degrees (56.67 degrees Celsius) in Death Valley in July 1913, but some experts dispute that measurement and say the true record is 130 degrees recorded there in July 2021.

Since late spring, numerous wildfires have broken out across California. The fires are largely eating grasses that have grown during successive wet winters and have now dried out.

Most of the fires remained small, but some have grown large. The largest active fire is the Basin Fire in the Sierra National Forest, where nearly 57 square kilometers have burned since late June. As of Friday, it was 46 percent contained.

Patch writer Paige Austin contributed to this report.