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California wildfires at risk of sparking as wind blows in
South Lake Tahoe resident Connor Jones sits with his dog on a smoke-cloaked empty beach in South Lake Tahoe, Calif., Monday Sept. 6, 2021. Residents who fled South Lake Tahoe under threat of a wildfire were allowed to return as crews stalled the flames from advancing. Credit: AP Photo/Samuel Metz
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South Lake Tahoe resident Connor Jones sits with his dog on a smoke-cloaked empty beach in South Lake Tahoe, Calif., Monday Sept. 6, 2021. Residents who fled South Lake Tahoe under threat of a wildfire were allowed to return as crews stalled the flames from advancing. Credit: AP Photo/Samuel Metz
A weather system approaching northwest California was expected to bring dry lightning and blustery winds by late Thursday, unleashing a risk of new wildfires as thousands of firefighters have been making headway against existing blazes.
A warning for dangerous fire weather was set to take effect in much of fire-scarred Northern California in the afternoon and last through Friday.
"The combination of isolated dry lightning and gusty winds with the dry fuels will bring the potential for critical fire weather conditions," the National Weather Service said.
A historic drought and recent heat waves tied to climate change have made wildfires harder to fight in the American West. Scientists say climate change has made the region much warmer and drier in the past 30 years and will continue to make weather more extreme and wildfires more frequent and destructive.
The California Department of Forestry and Fire Protection said Wednesday that firefighters were making significant progress against the flames in part because weather had improved.
More than 14,600 firefighters were on the lines of 13 active, large wildfires in California on Thursday.
The Dixie Fire in the northern Sierra Nevada and southern Cascade Range grew to nearly 1,449 square miles (3,753 square kilometers) but was 59% contained. It is the second-largest California fire on record. Only last year's August Complex was larger, at just over 1,613 square miles (4,177 square kilometers).
In this Sept. 1, 2021, file photo, a firefighter lights a backfire to stop the Caldor Fire from spreading near South Lake Tahoe, Calif. An unidentified firefighter has died of an illness while assigned to one of California's largest wildfires, authorities said Sunday, Sept. 5, 2021, marking the first death in a season that has seen blazes destroy thousands of buildings and force entire towns to flee. Edwin Zuniga with the California Department of Forestry and Fire Protection said he couldn't provide other details on the death. Credit: AP Photo/Jae C. Hong, File
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In this Sept. 1, 2021, file photo, a firefighter lights a backfire to stop the Caldor Fire from spreading near South Lake Tahoe, Calif. An unidentified firefighter has died of an illness while assigned to one of California's largest wildfires, authorities said Sunday, Sept. 5, 2021, marking the first death in a season that has seen blazes destroy thousands of buildings and force entire towns to flee. Edwin Zuniga with the California Department of Forestry and Fire Protection said he couldn't provide other details on the death. Credit: AP Photo/Jae C. Hong, File
In this Wednesday, Sept. 1, 2021, file photo, firefighters are lit by a backfire set to prevent the Caldor Fire from spreading near South Lake Tahoe, Calif. Thousands of wildfires burn in the U.S. each year, and each one requires firefighters to make quick decisions, often in difficult conditions like high winds and lightning. Crews and managers must determine when to bring in aircraft, what time of day is best to battle flames, whether to evacuate residents and even if certain fires should be extinguished at all. Credit: AP Photo/Jae C. Hong, File
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In this Wednesday, Sept. 1, 2021, file photo, firefighters are lit by a backfire set to prevent the Caldor Fire from spreading near South Lake Tahoe, Calif. Thousands of wildfires burn in the U.S. each year, and each one requires firefighters to make quick decisions, often in difficult conditions like high winds and lightning. Crews and managers must determine when to bring in aircraft, what time of day is best to battle flames, whether to evacuate residents and even if certain fires should be extinguished at all. Credit: AP Photo/Jae C. Hong, File
Near Lake Tahoe, the Caldor Fire grew only slightly, to just over 340 square miles (880 square kilometers), and was 53% contained.
Nationally, some 22,000 firefighters were working on 79 active, large wildfires in nine states in the West as well as Minnesota, according to the National Interagency Fire Center in Boise, Idaho.
President Joe Biden will survey fire damage during a visit to California next week.