Strong northeasterly winds known as Santa Ana will howl through the mountains and canyons of Southern California Wednesday through Thursday, sparking a wildfire threat not seen in the region in years, AccuWeather meteorologists warn.

The combination of high pressure building over the Northwest and strong winds at the level of the atmosphere where the jets travel over the Southwest will produce a moderate Santa Ana event for Southern California.

“Winds will increase later Tuesday evening and then continue through Wednesday and into Thursday,” AccuWeather senior meteorologist John Feerick said. “The strongest winds will be on Wednesday.”

Northeast winds will often gust to 50-60 mph, but strong gusts near 80 mph are forecast in the mountains, with an AccuWeather Local StormMax™ of 100 mph.

Such strong gusts can cause property damage and significant damage to poorly constructed buildings, Feerick warned.

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“The big risk will be a sharp increase in wildfire potential not seen in recent years, with the possibility of downed power lines, sparks and igniting fast-moving fires,” Feerick said.

The National Weather Service's Storm Prediction Center has issued the highest fire risk level of “Extreme Critical” in areas including Santa Clarita, Thousand Oaks, Simi Valley, Camarillo and Moorpark, California. This is the first extreme fire warning in California since December 2020.

“Santa Ana winds will be problematic in portions of Orange, Ventura, Santa Barbara and northwest Los Angeles counties,” Feerick said. “Much of the Los Angeles metropolitan area lies in a bowl-like formation and will be reasonably protected from the strong winds.”

Gusts will roar over the ridges and passes and continue through the northeast-southwest oriented canyons to the Pacific coast. In addition to the risk of fire, there is the possibility of vehicles overturning at high altitudes and dust being kicked up, which can suddenly reduce visibility.

Any forest fire that breaks out can get out of control almost instantly and spread extremely quickly, endangering a significant number of lives and property.

Winds in Santa Ana will decrease later Thursday and the risk of new fires igniting will decrease. However, any forest fires that may break out could last over the weekend.

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