How Santa Ana winds fueled the deadly fires in Southern California
(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.)
Jon Keeley, University of California, Los Angeles
(THE CONVERSATION) Powerful Santa Ana winds, with gusts reaching hurricane strength, swept down the mountains outside Los Angeles and spread wildfires into several neighborhoods in early January 2025, creating a terrifying scene.
Thousands of homes and other structures, including several schools, had burned by Jan. 11. At least 11 people had died, and the fires, which started Jan. 7, were still burning days later. Officials had urged more than 180,000 residents to evacuate. When the winds were strongest, there was little firefighters could do to control the flames.
Jon Keeley, a research ecologist in California with the U.S. Geological Survey and adjunct professor at UCLA, explains what causes extreme winds like this in Southern California, and why they create such a dangerous fire risk.
What causes the Santa Ana winds?
The Santa Ana winds are dry, powerful winds that blow down the mountains toward the Southern California coast. The region sees about 10 Santa Ana wind events a year on average, typically occurring from fall into January.
When conditions are dry, as they are right now, these winds can become a severe fire hazard.
The Santa Ana winds occur when there...