Once again, a red flag warning signifying a high risk of wildfire will be in force in much of Southern California Tuesday and Wednesday because of stiff Santa Ana winds, above-normal temperatures and low humidity levels.
The warning, which was scheduled to take effect at 5 a.m., was scheduled to remain in force until 8 p.m. Wednesday, and both wind and heat advisories were also issued. Much of the region was also under a red flag warning and wind advisories on Monday.
Red Flag parking restrictions designed to keep fire trucks moving freely on narrow hilly streets will be in effect today in Los Angeles and Pasadena on orders from the two cities' fire departments.
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Temperatures will likely be 10-20 degrees Fahrenheit above normal, humidity levels will be in the single digits through Thursday, and the warmest days of the current heat wave will be Wednesday and Thursday, when temperature highs in the 100s are likely in several communities, according to National Weather Service forecasters.
"The combination of gusty Santa Ana Winds, hot temperatures and single- digit humidities will bring extreme fire danger to the region through mid week," warned an NWS advisory. "A combination of strong winds, low relative humidity and warm temperatures will create extreme fire behavior."
The latest red flag warning was issued for the San Gabriel Mountains in Los Angeles and Ventura counties, the Los Padres National Forest in Ventura County, L.A. County's Angeles National Forest, the Santa Monica Mountain Recreational Area, the San Fernando, Santa Clarita and San Gabriel Valleys, L.A. County beachside cities, downtown L.A. and the rest of metropolitan Los Angeles, the Hollywood Hills and Orange County.
Winds of between 20 and 35 miles per hour gusting to 55 mph are expected in the mountains while in the valleys the wind will blow at between 15 and 25, with 35 mph gusts, forecasters said. Along the coast and in metropolitan Los Angeles, 2-30 mph winds are expected, along with 40 mph gusts.
Forecasters warned that the wind could make driving difficult, with Pacific Coast Highway, U.S. 101 and Interstate 405 likely to be affected. Motorists were warned to beware of crosswinds, particularly when at the wheel of a high-profile vehicle or tugging a trailer. Downed tree limbs and high power lines also could be a problem.
In explaining the patterns behind the threatening conditions, an NWS advisory stated that "a strong upper-level high-pressure system will persist off the California coast on Tuesday and edge closer to the region through mid week."
The weather service warned residents to protect themselves and others from the conditions by staying cool and hydrated, checking on their neighbors -- especially the elderly -- and never leaving kids or pets in cars parked in the heat with their windows rolled up.
The NWS forecast highs today of 79 on Mount Wilson; 86 in Lancaster, 87 in Palmdale; 88 in San Clemente; 89 in Avalon; 91 in Newport Beach; 93 in Laguna Beach; 94 at LAX; 95 in Saugus; 96 in San Gabriel, Burbank and Woodland Hills; 97 in Pasadena, Yorba Linda, Mission Viejo, Irvine and Anaheim; 98 in Fullerton; 99 in downtown L.A.; and 100 in Long Beach. No cooling trend is expected until Friday.