A red flag warning issued because of “extreme” fire weather conditions characterized by powerful Santa Ana winds, very low humidity levels and an abundance of bone-dry vegetation will remain in effect in much of Southern California until 6 p.m. Thursday, although it has been lifted earlier than scheduled in Orange County.
“Strong Santa Ana winds gusting between 40 and 60 mph will continue to impact wind-prone areas of Los Angeles and Ventura counties through Thursday morning, with isolated gusts to 70 mph in the Los Angeles county mountains, including the western portions of the Santa Monica mountains,” advised a National Weather Service statement. “Very dry air is associated with these Santa Ana winds with widespread single-digit humidities through Thursday, as low as 1 to 2% in some locations.”
“These prolonged dangerous fire weather conditions combined with the very dry fuels and presence of existing fires and associated flare-ups adds up to extreme red flag conditions for much of Los Angeles and Ventura counties. As a result, there is high potential for very rapid fire growth and extreme fire behavior with new or existing fires.”
The warning will be in force in the Santa Monica Mountains Recreational Area, the San Gabriel Mountains, the Angeles National Forest as well as mountain and forest areas of Ventura County — all areas where northeast winds will blow at sustained speeds of 25-40 miles per hour, producing gusts of 60 miles per hour and, at times, 70 mph, said NWS forecasters. At he same time, the humidity will be down to between 1 and 6 percent.
“If fire ignition occurs, conditions will be favorable for extreme fire behavior, long range spotting, and very rapid fire spread, which would threaten life and property. The strength of the expected winds could result in downed trees and power lines as well as power outages,” according to the statement.
The red flag warning will also be in force in the San Fernando and Santa Clarita valleys and valley and coastal areas of Ventura County amid northeast winds of 20-30 mph and 50-mph gusts through Thursday morning. Isolated gusts of up to 60 mph are expected in the hills. Humidity levels in those areas will also be between 1-6%.
Additionally, the red flag warning is in effect in the San Gabriel Valley, the L.A. coast and metropolitan Los Angeles, including Downtown L.A. Northeast winds of 15 to 25 mph with gusts of up to 40 mph will buffet the hills and canyons of coastal L.A., then weaken in the afternoon.
In Orange County, where the red flag warning was to be in effect through much of Thursday, it was canceled around 10 Wednesday night because, according to the NWS, “winds have weakened significantly.”
In the Antelope Valley, a hard-freeze warning went into effect at 1 a.m. Thursday and will expire at 10 a.m. Friday amid sub-feezing morning temperatures of 18-25 degrees.
Sunny skies were forecast in L.A. County Thursday, along with highs of 65 degrees on Mount Wilson; 66 in Lancaster; 67 in Palmdale; 72 in Saugus; 75 in Avalon;78 in Burbank and San Gabriel; 79 at LAX and in Woodland Hills; and 80 in Downtown L.A., Long Beach and Pasadena. Temperatures will remain about the same until Monday, when a cooling trend will get underway.
The NWS also forecast sunny skies in Orange County Thursday and highs of 59 on Santiago Peak; 70 on Ortega Canyon at 2,600 feet; 72 in Laguna Beach; 74 in Newport Beach and San Clemente; 77 at Trabuco Canyon and Fremont Canyon; 78 in Yorba Linda; 79 in Mission Viejo; 80 in Fullerton and Anaheim; 79 in Mission Viejo; 80 in Fullerton and Anaheim; and 81 in Irvine. Temperatures will remain at roughly the same levels amid sunny skies through at least Wednesday.