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Since last Tuesday, a series of ferocious wildfires have broken out in Southern California, with fast-moving flames raging through the Los Angeles area, killing at least and forced tens of thousands to flee their homes.

The state has been grappling with a prolonged drought in recent months, leaving vegetation parched, according to Andrew Winters, assistant professor in the Department of Atmospheric and Oceanic Sciences at CU ºù«ÍÞÊÓƵ. On top of that, the region’s strong winter winds have accelerated the spread of fires and made containment efforts extremely difficult.

The Palisades fire, the largest and most destructive, which has burned more than 23,000 acres along the Pacific Coast, is only as of Monday. The Eaton fire, northeast of L.A., burned down as many as , and is .

The fires’ proximity to densely populated areas could make them one of the costliest wildfires in California history.

Andrew Winters

With dangerous winds expected to return to the area today, CU ºù«ÍÞÊÓƵ Today sat down with Winters to discuss the role of winds in the fires, how climate change might have influenced fire risks in the West and what individuals living in fire-prone areas can do to prepare for a potential evacuation.

What contributed to the rapid spread of the L.A. fires?

California had a really wet year last year because of the strong El Niño event. They had heavy amounts of rain that allowed for subsequent growth of grasses and plants around the region.

Since this summer, as we've transitioned out of an El Niño into a La Niña, conditions have dried out considerably. Usually this time of year, California would see a fair amount of rain, but we barely saw any this winter. In fact, California is looking at some of their driest conditions on record over this period.

The lack of rainfall has allowed for the growth that occurred last year to dry out. The dried vegetation became particularly susceptible to wildfires and at the same time provided a lot of fuel for wildfire growth.

Then the strong Santa Ana winds blowing in the area created a condition that allowed these fires to take off and spread quickly.

What are the Santa Ana winds?

The Santa Ana winds are an intermittent strong wind flow that blows from Nevada and Utah into Southern California almost every year from fall to the early part of winter.

They are part of a normal weather pattern commonly observed in the Los Angeles area. What's rare about this particular situation is that these winds are occurring within an environment that has been suffering from a severe drought.

How are the winds making firefighting more difficult?

The winds create hostile environments for firefighters. When some of the fires in California first started, the winds were gusting to 80, 90 or even 100 miles an hour— similar to that of a Category 2 or 3 hurricane.

During the 2021 Marshall fire here in Colorado, winds were also blowing at 100 miles an hour, and that allowed the fire to spread rapidly and become highly destructive.

Things also got more difficult as the L.A. fires moved into an urban location. The burning of structures and their contents can release considerable harmful nonorganic chemicals into the atmosphere.

Moreover, the wind can take embers and spread them far away from the current location of the fire. This can lead to rapid development of wildfire spread that gets out of hand very quickly.

Does climate change play a role in causing these fires?

It’s tough to say at this point whether the Santa Ana wind pattern is becoming more or less frequent under climate change. But research has shown that climate change is increasing the intensity and frequency of .

We’re expecting droughts to become drier and more exacerbated under future climate scenarios. So climate change is likely involved in the development of the antecedent drought that's created more susceptible fuels for wildfires to start.

Additionally, some research has suggested that climate change could increase the likelihood of whiplashes between very wet periods to very dry periods. Such conditions allow for periods of intense growth of grasses that will then dry out. That means we might have more fuel available to burn if there’s a fire.

Lastly, as the climate warms, more water tends to evaporate from the ground and vegetation, causing fuels like grasses to dry out faster than they would in a cooler climate.

Can we predict these conditions in advance to reduce damage?

Prior to the fires, forecasters at the National Weather Service had done a really good job predicting these strong winds. There was an indication multiple days in advance of very critical fire weather conditions, both in terms of the dry fuels and the strong winds that may accelerate rapid fire spread. It's just unfortunate that the fire transpired into a remarkably catastrophic event.

In a lot of these cases, with strong winds that promote rapid wildfire spread, you may only have a couple of minutes to evacuate. For individuals, there's just not going to be enough time to work through everything you might want to pack up and bring with you.

So start taking some time to think ahead and prepare a go-bag . That includes not only what's important and valuable to you, but also thinking about how are you going to take care of pets and kids, and potentially your neighbors who may have less ability to move quickly. 

Planning ahead and knowing how to act when you need to is probably the best way to go.