Hurricane force winds are fanning the flames of the Southern California wildfires. What are Santa Ana winds?
At least five wildfires are ravaging Southern California, and the three largest have already killed at least five people, burned tens of thousands of acres and prompted the evacuation of an estimated 179,000 residents. Santa Ana winds coupled with dry conditions have created the perfect storm for the fires to spread.
Hurricane-force winds have fanned the flames of the Palisades Fire, currently burning on the west side of Los Angeles County in coastal communities including Pacific Palisades and Malibu. The winds are also blowing the embers of the Eaton Fire, which is impacting the cities of Pasadena and Altadena in northeast L.A. County.
What are Santa Ana winds?
Santa Ana winds flow east to west through Southern California's mountains, according to the National Weather Service. They begin when winds from the desert flow westward toward an area of low pressure, near the coast, like L.A.
The winds usually originate in the Great Basin of the United States between September and May. This area, east of California, is at a higher elevation than L.A., and as the air drops, its temperature rises, according to Dr. Robert Fovell, a UCLA professor of atmospheric and oceanic sciences.
These winds are more common in colder months when the desert air is cool. As the winds drop in altitude and increase in temperature, they also drop in humidity, causing a dryness. Vegetation can dry out and wildfires can start, with the winds fanning the flames.
How are Santa Ana winds impacting Southern California wildfires?
On Monday, the National Weather Service forecasted a strong Santa Ana winds event for L.A. through Friday, with the strongest gusts, which were likely to down power lines, arriving Tuesday and Wednesday,
Wind gusts peaked at over 75 mph Wednesday, according to CBS Los Angeles meteorologist Paul Deanno. Santa Ana winds are forecast through Friday, with another bout on Sunday, according to the weather service.
"Everyone needs to know that they are in danger because of these embers that are blowing from these just once-in-a-decade winds that are coming through our area, and they're still blowing," CBS News Los Angeles assignment editor Mark Liu reported Wednesday of the Palisades Fire.
As the winds picked up, so did the flames and Cal Fire reported the extreme gusts were posing a problem for firefighters, which have yet to contain any portion of the three biggest fires.
The windstorms and fires not only fueled the fires but also caused power outages for more than 1.54 million California homes and businesses as of Wednesday afternoon, according to utility tracker PowerOutage.us.
Drought is also very common in California and contributes to wildfire risk — and the extremes are exacerbated by climate change. In September, California Gov. Gavin Newson lifted the drought state of emergency in 19 counties, including several in Southern California. However, many areas of the state are still considered "abnormally dry" by the National Oceanic and Atmospheric Administration.
Southern California hasn't received more than 0.1 inches of rain since early May, the Associated Press reported. This combined with the strong winds have contributed to the spread of the massive fires.
Wildfire evacuations in Southern California
Evacuation orders or warnings were issued for tens of thousands of residents near the major fires in the region.
In the evacuation map, those in red zones are under an evacuation order and are required to evacuate. Those in lighter orange zones are under an evacuation warning and should prepare to leave at any time, per officials.
More than 1,000 structures have been destroyed and numerous injuries have been reported as a result of the fires.
