Editor’s Note (1/8/25): This story is being updated as the situation develops.
another explosive fire In California, driven by the well-known in the region Santa Ana windsit has burned hundreds of buildings and forced thousands from their homes. The Palisades Fire started at 10:30 a.m. Tuesday near the Pacific Palisades neighborhood of Los Angeles. Much of the neighborhood is under an evacuation order that extended north of Santa Monica. As of Wednesday afternoon, the fire had burned more than 15,000 acres and destroyed more than 1,000 structures.
Another fire, the Eaton Fire, broke out Tuesday evening in Altadena, California, north of Los Angeles. As of late Wednesday, it had burned more than 10,000 acres and caused at least five deaths. Both fires have caused many injuries, according to officials.
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On Wednesday afternoon, another fire broke out in the heart of Los Angeles, north of Hollywood. The fire quickly grew to about 20 acres as it spread downhill in Runyon Canyon. Although not as strong as Tuesday night’s wind, they were pushing the fire and carrying the embers that ignited the flames.
Forecasters warned that the fire risk was very high this week, reaching “particularly dangerous conditions” as strong winds combined with dry vegetation after a lack of rain at the start of what was usually a wet season.
Gusts around the Palisades Fire were measured in the 40- to 50-mph range as of Tuesday afternoon, climate scientist Daniel Swain said during his regular “climate and weather office virtual schedule,” scheduled. on YouTube. “Right now the winds are not very high, but then again they are high enough,” said Swain, of the University of California Agriculture and Natural Resources. Gusts were expected to reach 70 to 80 mph as winds peaked Tuesday night into Wednesday, with some areas seeing gusts of 100 mph. Gusts of 99 mph were measured in the San Gabriel Mountains north of Pasadena, California.
Santa Ana winds typically drive fast-moving, damaging fires in this area; their characteristic dryness and speed can quickly thicken and spread flames. These winds are the result of local geography and a particular weather configuration, where a high pressure system sits in the interior of the US West over the Great Basin and a low pressure system hangs over California or the sea. They “want” the winds to pass from high pressure to low pressure, and as they do so in this area, they move downslope from relatively high deserts. This descent compresses the air, heating it and drying it. (These downslope winds that occur in other parts of the world are scientifically called katabatic winds).
Santa Ana winds are channeled through narrow mountain canyons, which accelerates them. Due to the hot, dry and fast nature of these winds, they are perfectly suited to spread the flame from any spark that ignites. Wind blows embers ahead of the fire front, starting new fires. “Those turns will follow the wind and burn what they want,” Swain said another video on YouTube on tuesday
In some ways, this Santa Ana wind event is unusual: “It’s particularly extreme and reaching lower altitudes than usual with strong winds,” Swain said. another lecture on Wednesday morning.
The schedule of the event is consistent with the usual: Santa Ana events usually take place between October and January. Part of the resulting fire hazards from these events, however, is related to the impact of climate change on regional rainfall fluctuations.
Fires in this area don’t burn in forests, grasses and brush, and the amount of that vegetation “varies a lot … depending on how much precipitation actually happened before the growing season,” Swain explained in his video Wednesday. The last two rainy winter seasons were very wet, so there has been plenty of fuel. Meanwhile, last wet winter was followed by an unusually hot summer, and this winter had a very warm start, as well as the “driest start to winter on record,” so all that fuel has been primed to ignite, he added. .
With a changing climate, we expect wet periods to become wetter than in the past and dry and hot periods to become drier and hotter. This could lead to more years where heavy vegetation growth overlaps more and more with the Santa Anas after major droughts, creating more opportunities for rapid and destructive wildfires.
In addition to the Palisades and Eaton fires, the Hurst Fire, which has burned 500 acres in the Sylmar neighborhood of Los Angeles in the San Fernando Valley, also broke out Tuesday afternoon.
The exact causes of the fires are not yet clear, but there was no lightning nearby, and Most fires in California are human-causedmostly by accident.
On Tuesday, Traci Park, a member of the Los Angeles City Council that includes Pacific Palisades, said the fire would likely burn hundreds of buildings. according to New York Times. “This will be a devastating, devastating loss for all of Los Angeles,” he said. Officials have reported at least two deaths and multiple injuries in the fires.
Looking at the smoke signature of the wildfires on radar in his video Wednesday, Swain noted that it’s a “tremendous volume of smoke” not normally seen burning brush and grass. “I suspect there will be whole neighborhoods on fire,” he said.
The Palisades Fire reported burning vegetation on the grounds of the Getty Museum in Los Angeles, “but no structures are on fire, and staff and collections remain safe,” the museum said. X said to himself (formerly Twitter). The museum will be closed until January 13th. NASA’s Jet Propulsion Laboratory was shut down Wednesday due to the Eaton fire. The facility is located in La Cañada Flintridge, California, which is according to an evacuation order.
While the winds are expected to slowly die down Wednesday, Swain said there is still a risk of the fire spreading. Humidity levels will drop and temperatures will rise, so fire movement will be more land-based, which could change the areas of greatest threat and present firefighting challenges.
