Gusty Santa Ana winds and “very low humidity” will combine to create “widespread critical fire weather conditions” in much of the Southland from early Thursday through Friday afternoon, the National Weather Service said Wednesday.
Wind gusts of between 45 and 70 miles per hour are expected from mid-morning Thursday to mid-afternoon as humidity levels fall to between 3 and 10 percent, it said.
Given an abundance of dry vegetation, “critical fire weather conditions are expected,” the NWS said in a statement.
The red flag warning will be in force in the San Gabriel and Santa Monica mountains and the Angeles National Forest — areas where winds blowing at a sustained 25 to 45 mph are expected, along with 70-mph gusts and humidity levels of 3-10 percent — from 3 a.m. Thursday until 6 p.m. Friday.
The warning will also be in force at the same time in the San Fernando, Santa Clarita and San Gabriel valleys, along the L.A. County coast and in metropolitan Los Angeles, including Downtown L.A. Additionally, it will be in effect in much of Ventura County, including the Los Padres National Forest adjoining the Angeles National Forest, and in coastal Orange County from 3 a.m. Thursday until 8 a.m. Friday.
“If fire ignition occurs, conditions may be favorable for extreme fire behavior, which would threaten life and property,” according to the statement.
The Santa Anas result from high pressure over Nevada, said NWS meteorologist Rich Thompson, while the low humidity is caused by cold dry air and a drying-out effect that occurs when winds blow across mountain slopes.
Southern California Edison, meanwhile, cautioned some customers that they could lose power. It said it may order “Public Safety Power Shutoffs” aimed at reducing fire risks. Edison officials noted Tuesday that the power cuts — which would de-energize lines that might be in danger of being damaged and igniting fires in high-wind conditions — are only “under consideration.”
But Southern California Edison said Wednesday it has given Malibu a 48-hour notice that a Public Safety Power Shutoff may be implemented that could affect Western Malibu beginning Thursday at 9:00 PM to Friday at 9:00 AM. Individuals who are medically dependent on electricity service should consider proactively staying in another area until conditions change.
Residents are encouraged to check on family members and neighbors who may need assistance, Edison urged. If a PSPS is implemented, and the hazardous conditions have passed, it could take 24 to 72 hours to re-energize circuits because SCE must first inspect all powerlines in the affected area to ensure they are safe to re-energize.
According to the utility, more than 106,000 customers throughout SCE’s service area live in the neighborhoods being considered for potential rolling power cuts.
In Los Angeles County, there are roughly 30,700 customers facing possible cuts, primarily in the northern reaches of the county such as Lancaster, Palmdale, Santa Clarita and areas such as Acton, Agua Dulce, Lake Hughes and Canyon Country. San Fernando is also included in the potentially affected area.
Cal Fire announced that it is increasing staffing over the coming days to be prepared for potential wildfires, but the Los Angeles Fire Department did not order red flag parking restrictions on narrow hilly streets.
“With some of the most destructive and deadliest fires occurring October through December, we need Californians to not be complacent,” Cal Fire Chief Thom Porter said. “Wind-driven fires move fast, and residents need to be ready to evacuate at a moment’s notice in the event of a wildfire. We have increased our staffing, but need the public to remain vigilant. It is important to follow evacuation orders and leave early as fires move very fast under these conditions.”
The NWS forecast mostly cloudy or partly cloudy skies in L.A. County Wednesday and highs of 66 degrees on Mount Wilson; 72 degrees in Avalon and at LAX; 73 in Long Beach; 75 in San Gabriel and Burbank; 76 in Downtown L.A.; 78 in Woodland Hills and Saugus; and 83 in Palmdale and Lancaster. Wednesday’s temperatures will be up to 10 degrees higher and climb a few more degrees Friday, when both Pasadena and Woodland Hills will hit highs of 87.
The NWS forecast a combination of sunny and partly cloudy skies in Orange County and highs of 65 on Santiago Peak; 68 on Ortega Highway at 2,600 feet; 69 in Laguna Beach; 70 in San Clemente; 73 in Newport Beach and Trabuco Canyon; 74 in Mission Viejo; 75 in Fremont Canyon, Yorba Linda and Fullerton; 76 in Anaheim; and 77 in Irvine. Temperatures will be up to seven degrees higher Thursday and five degrees higher than that on Friday.