Southern California faces extreme fire danger as Santa Ana winds roar

Forecasters described the fire danger taking aim at Southern California as "extremely critical" Thursday afternoon, and power crews were faced with decisions on whether to risk leaving the electricity on in some communities. Even though the strongest winds have passed, the fire danger will remain substantially elevated into Saturday.

"Strong winds and low humidity are combining for a long-duration of critical fire danger," said AccuWeather Senior Meteorologist Dave Houk.

The National Weather Service's Storm Prediction Center issued their highest level of fire danger, "extremely critical", through Thursday across the high terrain just east of San Diego, as well as the mountains of eastern Ventura and western Los Angeles counties. Over 7 million Southern California residents were also placed in the second highest "critical" fire danger category.

CalFire announced on Wednesday that they increased the number of engines, bulldozers, hand crews, helicopters and air tankers across the region in preparation for the wind event.

CalFire also announced on Thursday afternoon that there are high winds impacting Southern California that are leading to an increase in wildfire activity, reminding residents that the wildfire danger is not over.

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Red flag warnings and wind advisories remain in effect across the region due to the ramp-up of Santa Ana winds. These winds are being generated as a strong high pressure system builds across the interior West and essentially funnels the air from the interior West into Southern California and then offshore.

"As the air flows through the canyons and passes, it will accelerate and gain even more speed blowing downhill from the mountains due to the effects of gravity," AccuWeather Senior Meteorologist Alex Sosnowski said.

Winds began to increase in earnest Wednesday night, with gusts past 80 mph reported in the Los Angeles County mountains. The windy weather caused a brush fire in Rancho San Diego to spread rapidly, prompting evacuations as several homes were burned in the flames, according to The San Diego Union-Tribune.

AccuWeather meteorologists expected winds to be at their peak through Thursday, but gusts high enough to keep the fire danger elevated are likely to persist into the early part of the weekend.

Gusts frequenting 30-50 mph are expected to continue to whip through mountains passes and even reach coastal areas and the waters and islands offshore. An AccuWeather Local StormMax™ of 75 mph is possible in the typical wind-prone areas through Friday morning.

Such winds threaten to down trees and power lines, as well as create rough surf and blowing dust.

"Sparks generated by downed power lines will threaten to initiate fires that can quickly escalate into major and fast-moving wildfires," Sosnowski said.

On Tuesday, Southern California utility companies were contemplating shutting off power to more than 300,000 customers due to the anticipated ramp-up of gusty winds, according to The Associated Press. As of early Thursday morning, more than 90,000 customers were without power across Southern California, mostly due to planned shutoffs.

Forecasters urge residents to avoid using open flames over the next couple of days, as well as to properly discard matches and cigarettes.

Although winds will turn less gusty as the weekend progresses, AccuWeather meteorologists say residents should not let their guard down as yet another moderate to strong Santa Ana wind event may kick up early next week.

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