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In Southern California, a rare extreme red flag warning is in effect. High winds make wildfires more dangerous. NPR's Kirk Siegler reports that scientists are linking wind conditions to climate change.
KIRK SIEGLER, BYLINE: This story about wildfires and extreme winds starts with snow.
DANIEL SWAIN: Supposed to get about a foot today.
SIEGLER: Climate scientist Daniel Swain is looking out his window at the National Center for Atmospheric Research in Colorado. The snow is piling up, and there's a rare prolonged arctic freeze gripping the Rocky Mountains. So what does that have to do with the dangerous California wildfires? It turns out, everything.
SWAIN: And it's that extremely cold air mass to the east of California that's driving the extreme winds and the extreme fire weather conditions in that state right now.
SIEGLER: Swain says the prolonged warming in the Arctic is forcing freezing air down into the Rockies, and that cold air mass is pushing dry winds off the desert into California.
SWAIN: What we've seen the last couple years is kind of a preview of what we expect the future to look like.
SIEGLER: These Santa Ana winds, or Diablos as they're sometimes called in Northern California, are common for fall. They tend to peak around now just as California's dry season is ending. But climate change is causing the traditional winter rainy season here to shorten dramatically, and Swain says California is a lot hotter.
SWAIN: It may not sound like much to have warmed two or three degrees over the past few decades in California. But that has brought about a profound increase in the flammability and the dryness of vegetation.
SIEGLER: Extreme winds like these make wildfires much harder to control, let alone even fight, especially as embers are igniting new fires more than a mile or more ahead of the initial wall of flames. That's why tens of thousands of people have faced evacuation orders across California. The wind-driven Getty Fire ignited in densely populated West Los Angeles early Monday. LA Fire Chief Ralph Terrazas warned the winds could reverse all the progress made building containment lines.
RALPH TERRAZAS: This is a record-setting event.
SIEGLER: And a big worry is that choppers will be grounded due to it being too dangerous to fly.
TERRAZAS: That is a drastic move, but it's for the safety of the pilots and their effectiveness.
SIEGLER: Now, it's remarkable that even in these extreme winds firefighters have knocked down hundreds of new fire starts. Forecasting has gotten a lot better. Fire managers are better prepared to deploy engines to the most at-risk neighborhoods ahead of the winds. The LAFD also has a lot of practice in a flammable city where neighborhoods are built into brush and wild lands. This is of some solace to 86-year-old Sue Willumsen (ph) who's sleeping on a cot at a Red Cross shelter in the Pacific Palisades neighborhood.
SUE WILLUMSEN: I walked down here with my cane and my few belongings that I needed.
SIEGLER: Willumsen says she understands why the authorities are being so cautious due to the winds.
WILLUMSEN: Especially for me, it's hard to get out. And I don't want to impose on anybody. I'd rather be safe than sorry.
SIEGLER: The extreme winds could linger through Thursday. Kirk Siegler, NPR News, Los Angeles. Transcript provided by NPR, Copyright NPR.