Thousands of lightning strikes spark wildfires in California
Numerous wildfires erupted in the central and northern regions of California on Tuesday during an outbreak of thunderstorms and dry lightning that some meteorologists had warned would spark new fires and intensify existing blazes.
The blazes spread quickly on Tuesday, while several large, intense forest fires have been burning in Northern California and in the Sierra Nevada over the past week.
The hazardous weather arrives after a hot Labor Day weekend that has further dried out a parched landscape during what is typically the peak of fire season in the state.
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New fires sparking
Dozens of fires ignited on Tuesday - so many that most were not initially given formal names but instead were identified by numbers. Many of the new blazes are in the foothills of the Sierra Nevada range in Tuolumne and Calaveras counties, which Cal Fire has dubbed the TCU September Lightning Complex.
The most threatening of these are the 6-5 Fire and the 2-7 Fire, both of which have forced evacuation orders. With thunderstorms forecast Tuesday evening through Thursday, more blazes are likely, particularly in the mountains of Northern California.
Several parts of Tuolumne County, including the town of Chinese Camp, were ordered to evacuate on Tuesday. Video footage shared by KCRA 3 News, a Sacramento broadcaster, showed destroyed homes and downed power lines in the town, a historic mining settlement once home to thousands of Chinese immigrants during the Gold Rush.
The National Park Service also warned visitors about smoky conditions in and around Yosemite National Park, a part of which is located in Tuolumne County. The popular park experienced unhealthy air quality levels for several hours Tuesday.
Earlier Tuesday, Cal Fire warned that lightning had already sparked dozens of new fires across the far-northern region of the state, urging residents to brace for critical fire weather from 1 p.m. to 9 p.m.
“Scattered lightning on extremely dry fuels is likely to spark new fires that can spread rapidly with gusty, erratic winds,” authorities said.
The sheer number of new fires, combined with gusty thunderstorm winds, makes it difficult for firefighters and firefighting aircraft to tackle every blaze, increasing the chances that any fire could rapidly grow out of control.
In addition to the new blazes, another major fire in California is the Garnet Fire, which sparked on Aug. 24 and has been burning intensely in the Southern Sierra, an area of high tree mortality and limited fire history. It is now over 28,000 acres in size.
The Dillon Fire in the Six Rivers National Forest in northwestern California stretches more than 8,000 acres.
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Weather fueling the flames
Meteorologists at the National Interagency Fire Center’s Predictive Services issued “high risk” designations for Northern California, warning of a new round of fires and “significant large fire growth” on both new and existing blazes.
They also warned of a “critical fire environment” with gusty winds, low humidity and hot, unstable conditions.
The high-risk zones were expanded on Tuesday morning to include the Sacramento Valley and areas farther south, such as the Sierra foothills, the Southern Sierra and even parts of the mountains near Los Angeles.
Moving north, the fire risk extends into Oregon and Washington, where red flag warnings are in effect until Wednesday evening. There is lightning potential in the Pacific Northwest through at least Friday amid a significant heat wave.
Wildfires have escalated during extreme heat that has made conditions highly flammable in many areas. In far northwestern California, for example, vegetation is at or near record-dry levels for the date.
The high temperature in Hanford in the Central Valley on Monday tied the 2022 record. Some locations in the San Francisco Bay Area also saw record-breaking temperatures over the Labor Day weekend.
Heat advisories were in place in Southern California into Tuesday evening, where inland temperatures between 95 to 100 degrees have been common recently.
This week’s thunderstorms have spawned from a surge of monsoon moisture from the southwest, combined with zones of low pressure spinning off the U.S. West Coast, which is helping to trigger and enhance storms.
The monsoon has arrived late in California and the Southwest this year.
Though recent rains have quelled fire risk in some mountain and desert areas of Southern California, conditions remain quite flammable in most of the state, particularly in valley and foothill locations, as well as in most of Northern California.
As California faces its most extreme drought in 1,200 years, forecasters have warned about the potential for dry thunderstorms - which produce virtually no rainfall on the ground - and the heightened risk for wildfires. In 2022, a rare barrage of 66,000 lightning strikes hit Southern California, triggering several additional spot fires.
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Grace Moon contributed to this report.