California faces ‘dangerous’ fire threat this weekend from high winds

Roaring, dry winds are forecast to bring “dangerous” fire weather to California beginning Saturday and lasting into early next week. It’s a reminder that, despite an extremely wet winter and a dousing from Tropical Storm Hilary in August, fire season isn’t yet over in the state. Strong autumn winds, such as Santa Anas, can shift the fire season and have typically driven California’s most serious wildfires.
The risk appears to be greatest in Southern California, particularly in the Los Angeles area, where fire weather watches and high wind watches have been posted ahead of the strongest wind event of the season so far.
“This is a high confidence, very significant event for Saturday night through Monday, especially from a Fire Weather standpoint,” the Los Angeles Weather Service wrote in a discussion on Friday. “Residents in the Fire Weather Watch area, especially those in high fire danger locales, need to get ready now in case a fire starts or power loss materializes.”
The utility Southern California Edison is considering cutting power to about 150,000 customers across five counties – Los Angeles, Ventura, Orange, Riverside and San Bernardino – to prevent electrical equipment from sparking a wildfire during the wind event. Customers in high-risk areas have been notified of possible ‘Public Safety Power Shutoffs,’ but their scope is subject to change as conditions evolve, Jeff Monford, a spokesperson for the utility, said.
For northern California, it is likely the strongest offshore wind event of the last two years. Red flag warnings for fire danger blanket much of the region from early Saturday morning through 5 p.m. Sunday, including the San Francisco Bay Area, where winds of up to 60 mph could reach higher mountain peaks, along with very low humidity. However, the risk will be offset by recent rains, and vegetation is not nearly as flammable as it has been during notorious wind-driven wildfires of the last several years. Devastating autumn firestorms struck communities in northern California in 2017, 2018 and 2020.
The upcoming windy conditions are a result of what’s called a classic “inside slider” weather system. A cold front and associated high pressure zone in the northern Rockies and the Intermountain West are setting up a large change in pressure over a small area, driving winds and very dry air into California.
So far, it’s been a mild autumn in California without serious fire weather, fluctuating between cool, moist weather and warmer periods. Although the state is essentially drought-free and vegetation contains more moisture than normal for this time of year, dry winds can quickly desiccate the abundant grasses that grew during the wet winter.
It’s been over two months since Hilary drenched much of Southern California, and some areas, such as the Central Coast, largely missed out on significant rain. The storm brought a springlike flush of green to the region, but the landscape has been drying out for several weeks amid record-breaking heat at times.
“We haven’t had much rain since then,” said Eric Drewitz, a meteorologist with the Southern California Geographic Area Coordination Center in Riverside. “We’re not out of the woods until we get a good, season-ending rain system moving through.”
This weekend’s fire weather arrives as the state is preparing for storms and possible flooding during the upcoming El Niño winter, with odds tilting toward wetter conditions for December through February in California.