How supercharged Santa Ana winds are fueling California’s wildfire crisis

Three large wildfires — driven by strong Santa Ana winds — are sweeping through Southern California, forcing tens of thousands to flee and blanketing Los Angeles in smoke.

The Palisades, Eaton and Hearst fires had covered more than 5,600 acres of Southern California as of Wednesday morning. Mandatory evacuation orders were issued for tens of thousands, but the size of the fires increased overnight, aided by gusty Santa Ana winds.

ESA’s Copernicus Sentinel-2 mission captured the above image of the Palisades fire at 10:36 a.m. local time on January 7. Since then – just 24 hours ago – the fire has exploded in size alongside the two fires mentioned above. Officials warn that the fires are continuing to spread rapidly, due in large part to strong winds coming from the east.

Santa Ana winds and the “atmospheric hairdryer”

Santa Ana winds are easterly or northeasterly winds that blow toward the Pacific coast. Winds can occur several times during the year, but when combined with dry (low humidity) conditions, winds can spread to fires that could have been more easily managed.

As of Wednesday morning, the National Weather Service has issued a red flag warning for wildfires in Los Angeles until 4:00 p.m. PT, an air quality advisory in effect until 5 p.m., and a high wind warning until 6 p.m.

“The air dryer will dry things out even more, and because this will last several days, the vegetation will get progressively drier the longer the wind lasts,” said Daniel Swain, a climate scientist at the university. California, Los Angeles, at a university He releases. “So some of the strongest winds will be at the beginning of the event, but some of the drier vegetation will come in at the end, so the reality is that there will be a very long period of high fire risk.”

Perfect storm: dry vegetation, low humidity, gusty winds

Conditions on the ground—extremely dry vegetation—have primed the area for wildfire spread. But the real catalyst for the speed and unpredictable nature of fires is fast-moving winds. According to the NWS, northerly winds generally range from 30 to 40 mph (48 km/h to 64 km/h) with gusts up to 60 mph (97 km/h). The strongest Santa Ana winds can generate gusts of 100 mph (160 km/h); Indeed, officials recorded a 100 mph gust in the San Gabriel Mountains around 5 a.m. local time Wednesday, according to the National Weather Service.

“Today’s life-threatening wind storm shows how quickly extremely dangerous conditions can develop. Southern California has had a particularly hot summer, followed by no precipitation,” Alex Hall, director of UCLA’s Greater Sustainable Los Angeles Challenge, said in the same release. Almost as much rain as we normally have.” “All of this comes on the heels of two very wet years, which means there is plenty of fuel for potential wildfires.”

Besides pushing fires one way or another, winds can knock down trees and power lines, providing more ways for plants to catch fire and cause power outages in affected areas.

“These extreme winds have the potential to turn a small spark into a wildfire that consumes thousands of acres with alarming speed — a dynamic that is only exacerbated as temperatures rise in a changing climate,” Hall added.

What are forest fires and weather today

Although the Palisades Fire is the largest, covering about 2,900 acres, the Eaton Fire swelled overnight. Almost doubled Its volume in a few hours as of 6 AM PT.

Evacuation orders for the Eaton Fire expanded Wednesday morning to include the Altadena and Sierra Madre areas. NASA’s Jet Propulsion Laboratory at La Cañada Flintridge is also subject to this order, although the lab was already under a remote work notice as of yesterday.

Although the winds are expected to subside by late morning local time, they will remain strong and conditions suitable for wildfire spread will continue throughout the day.

as National Weather Service website WARNINGS If you see or smell smoke, it is recommended to stay inside with windows and doors closed, avoid intense physical activity outside, wear an N-95 mask if you must be outside, and turn on your air conditioner and/or air purifier. That is, of course, unless the fire is on your doorstep and local authorities have authorized an evacuation.