Editor’s note (January 8, 2025): This article has been updated as the situation evolves.
Another explosive wildfire in California, sparked by the region’s notorious Santa Ana winds, has burned hundreds of buildings and forced thousands of people to evacuate their homes. The Palisades Fire broke out at 10:30 a.m. local time on Tuesday near Los Angeles’ Pacific Palisades neighborhood. Evacuation orders have been issued for much of the neighborhood, including north of Santa Monica. As of Wednesday afternoon, the fire had burned more than 15,000 acres and destroyed more than 1,000 buildings.
Another fire, the Eaton Fire, broke out Tuesday night in Altadena, California, just north of Los Angeles. As of late Wednesday, more than 10,000 acres had been burned and at least five people had died. Both fires resulted in numerous injuries, officials said.
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Another fire broke out Wednesday night in central Los Angeles, just north of Hollywood. The fire spread rapidly, spreading downhill into Runyon Canyon and covering approximately 20 acres. Although the winds were not as strong as Tuesday night, they were still pushing the fire forward and carrying embers that could ignite.
Forecasters said the fire risk was extremely high this week, with the lack of rain at the start of the rainy season, combined with fierce winds and flaming dry vegetation, creating “particularly dangerous conditions”. It warned that it had reached .
Wind gusts around the Palisades fire were measured in the 40-50 mph range as of Tuesday afternoon, climate scientist Daniel Swain said during his regular “Virtual Climate and Weather Office Hours” hosted on YouTube. said. “The winds aren’t super strong right now, but they’re still strong enough,” said Swain, of the California College of Agriculture and Natural Resources. Winds are expected to peak between Tuesday night and Wednesday, with gusts expected to reach 70 to 80 mph and could reach 160 mph in some locations. Wind gusts of up to 99 mph were recorded in the San Gabriel Mountains north of Pasadena, California.
Santa Ana winds typically cause fast-moving, damaging fires in the region. Due to its characteristic dryness and speed, flames are fanned and spread rapidly. These winds are a result of the region’s geography and a particular weather setup with high pressure over the Great Basin in the interior of the western United States and low pressure over California or offshore. The winds “want” to move from high pressure to low pressure, and as they move through this region, they travel downward from relatively high deserts. This descent compresses the air, making it warm and dry. (Such downslope winds also occur elsewhere in the world, but scientifically they are called kabatic winds.)
Santa Ana winds also pick up speed as they pass through narrow mountain canyons. The hot, dry, and fast nature of these winds makes them perfect for spreading flames from any spark. The wind blows the embers well in front of the fire front, starting a new ignition. “The embers will carry in the wind and burn whatever they want,” Swain said in another video posted to YouTube on Tuesday.
In some ways, this Santa Ana wind phenomenon is atypical. “It’s particularly extreme, with strong winds reaching lower elevations than normal,” Swain said at a separate briefing Wednesday morning.
The timing of the event is consistent with normal, with Santa Ana events typically taking place from October to January. However, part of the increased fire danger from these events is related to the effects of climate change on rainfall variability in the region.
Fires in the area are burning in grass and brush rather than forest, and the amount of vegetation “depends a lot on how much precipitation we actually had before the growing season,” Swain explained in a video Wednesday. . The past two winters had been very wet, so fuel was plentiful. Meanwhile, a wet second half was followed by an unusually hot summer, and this winter has had a very warm start, “the driest start to winter on record,” so all that fuel is especially primed to ignite. He added that this has been done. .
As the climate changes, wet seasons are expected to become wetter than in the past, and dry and hot seasons are expected to become drier and hotter. This could lead to more years of significant vegetation growth followed by large dry spells that overlap with the Santa Anas Mountains, increasing the chance of fast-paced and catastrophic fires.
In addition to the Palisades and Eaton fires, the Hearst Fire, which has burned 500 acres in the Sylmar area of the San Fernando Valley near Los Angeles, broke out Tuesday night.
The immediate cause of the fires is not yet clear, but no lightning strikes occurred in the area, and the majority of California’s fires are human-caused and mostly caused by chance.
On Tuesday, Los Angeles City Council member Tracy Park, whose district includes the Pacific Palisades, said the fire would likely destroy hundreds of buildings. new york times. “This would be a devastating, devastating loss for all of Los Angeles,” she said. Authorities reported at least two deaths and numerous injuries in the fire.
“This is a huge amount of smoke,” Swain said in a video Wednesday showing smoke signatures from the fire on radar, noting that you wouldn’t normally see just burning brush or grass. “I think the whole neighborhood is probably on fire,” he says.
The Palisades fire reportedly burned vegetation on the grounds of the Getty Museum in Los Angeles, but “the building is not on fire and our staff and collections are safe,” the museum said on its X (formerly Twitter) account. Ta. The museum will be closed until January 13th. NASA’s Jet Propulsion Laboratory was closed Wednesday due to the Eaton Fire. The facility, located in La Cañada Flintridge, California, is under an evacuation order.
Swain said winds are expected to gradually ease Wednesday, but the risk of the fire spreading remains. As humidity levels fall and temperatures rise, fire movement will become more terrain-driven, potentially changing the areas most threatened and creating unique challenges for fighting fires.