SPOKANE, Wash. — An unusually hot and dry summer, ferocious lightning storms and a high pressure system pushing wind west across the Cascade and Sierra Nevada mountain ranges has created an explosion of wildfire across Western states.
More than 26,000 firefighters are battling 96 conflagrations across 12 Western states in a startling beginning to the traditional wildfire season.
The resulting images are apocalyptic: The skies have turned red in California. Sunsets are an eerie orange over much of Oregon and Washington. Tens of thousands of people have been ordered to evacuate. Smoke and smog hang over major cities as officials urge those at risk of respiratory trouble to stay indoors with the windows shuttered.
Lightning storms and high winds have set almost 2 million acres of California land ablaze, about 2 percent of the entire state. Fire crews are battling four fires that have burned more than 100,000 acres. Some of the biggest fires are large enough to create their own weather systems.
On Thursday, the California Department of Forestry and Fire Protection tweeted that the state had seen six of its top 20 largest wildfires this year.
More than half a million acres in Washington state are burning, including the entire town of Malden, about 35 miles south of Spokane. Several fires burning on the Okanagan Plateau have burned more than 100,000 acres, threatening the cities of Omak, Okanagan and Davenport.
Oregon Gov. Kate Brown (D) said Wednesday that five small towns were “substantially destroyed.” At least seven people have died in Pacific Coast states, and more deaths are likely to be confirmed in the coming days.
Large fires are raging in Colorado and Oregon, while crews fight to contain smaller fires in Alaska, Arizona, Idaho, Montana, Nevada, New Mexico, Utah and Wyoming before they burn out of control.
“Firefighters across the western states are seeing extreme fire behavior on many large fires,” the National Interagency Fire Center, based in Boise, said in a statement Wednesday.
Fire experts say climate change and recent weather patterns have created the conditions in which the annual fire season is becoming longer and more explosive. Summers are hotter, drying out fuels that lie on forest floors. The atmosphere is drier, even in rainy areas on the Pacific Coast. The heat creates instability that can lead to high winds that can make even a small fire burn out of control in a matter of minutes.
“When we have really warm dry summers, more of our landscapes on both sides of the mountains have a lot of those available fuels, so they’re primed for a fire,” said Susan Prichard, a fire ecologist at the University of Washington. “With climate change, with warmer drier summers and longer associated fire seasons, we’ve just got more opportunities” for large fires.
More immediately, lightening storms have ignited blazes in California, Oregon and Washington. A high pressure system east of the mountains has pushed hot dry air to the west, a phenomenon that creates systems known as the Santa Ana and Diablo winds in California and the East winds in Oregon and Washington.
“The lightning obviously was a weather factor that just started so many fires simultaneously throughout California. Not only that, but we had several prolonged periods of extreme heat that helped dry the vegetation out that helped make it more readily ignitable,” said Geoff Belyea, the fire chief in California’s Napa County.
Earlier this month, Napa County experienced 38 fires in a 48-hour window, Belyea said. Crews put out 35 of those fires quickly. The largest fire in the region, the LNU Lightning Complex fire just north of St. Helena, is 91 percent contained after burning more than 375,000 acres.
Sparks from the lightening storms ignited many blazes, but some were started by human activity. A pyrotechnic device at a gender reveal party in Northern California sparked the El Dorado fire, which has burned 11,200 acres.
The scenes of devastating fires, of cities under blankets of pollution and of ash falling in some of the country’s largest cities are becoming an annual event, as the climate warms and environmental conditions change.
“It is becoming more usual to have this intense fire activity,” said Ken Pimlott, the former chief of CalFire. “An aligning of everything can make just a catastrophic event.”
Fire crews from across the West are getting assistance from the Department of Defense and from Canadian firefighters who have deployed across the border. More than 200 soldiers from an engineer battalion based at Joint Base Lewis-McChord have deployed to the August Complex fire in California, the largest fire currently burning; aircraft have been deployed by the Washington, California and Wyoming Air National Guards to support fire fighting operations.
The number of fires burning to date and the number of acres burned are both below the 10-year average through Sept. 9, according to the National Interagency Fire Center. But that 10-year average over the last decade is substantially higher than previous decades, when only a fraction of the number of fires and acres burned, a sign of the changing climate.
“Our 10-year average has been staggering and looks nothing like the 1970s and 1980s,” Prichard said.
The typical fire season, too, is getting longer. In some areas, fire season is now year-round.
“As we’re seeing warmer and drier temperatures as the climate warms, we’re seeing an increase in the window of time that fires are able to ignite and spread,” said Brian Harvey, a forest fire ecology expert at the University of Washington’s School of Environmental and Forest Science. “Even though we have not exceeded the record-breaking trends West-wide, I think what’s been most surprising and most alarming is the rapid increase in total area burned just over the last 48 to 72 hours because of this weather system.”
The massive conflagrations in the first few days of September portend a long, hot and dangerous season in the months ahead.
“We’re not done. We’re only in the first two weeks of September. We have a long way to go, and our firefighters collectively are being pushed,” Pimlott said. “We knew this was coming. Nothing’s going to change the vegetation before winter, so we could see another siege like this.”