LOS ANGELES - A red flag warning signifying a high risk of wildfire will be in effect Monday in the San Gabriel Mountains, the Angeles National Forest, the Santa Clarita Valley and several areas of neighboring Ventura County because of strong winds, high heat and low humidity at the start of another heat wave, the Southland's first of fall 2020.
"Critical fire weather conditions are anticipated across the mountains of Ventura and Los Angeles counties as well as the Santa Clarita Valley Monday morning through Monday afternoon," warned a National Weather Service statement. "North to northeast wind gusts between 30 and 45 mph are expected along with relative humidity dropping into the teens and single digits. Therefore, red flag warnings have been issued for these areas from 5 a.m. Monday through 5 p.m."
The weather Service said offshore winds combined with hot and dry conditions will bring elevated to brief critical fire weather conditions Tuesday through Friday in areas away from the coast, including an increased threat of plume-dominated fires with extreme fire behavior at times.
In the Santa Clarita Valley and the San Gabriel Mountains, a wind advisory will be in effect from 3 a.m. to 3 p.m. because of expected northeast winds of 20 to 25 miles per hour and gusts of 40 mph amid triple-digit temperatures.
"Gusty winds will blow around unsecured objects and make driving difficult, especially for high-profile vehicles' warned the NWS. "Tree limbs could be blown down and a few power outages may result. Hot temperatures may cause heat illnesses to occur."
Additionally, a heat advisory issued because of high temperatures will be in force from 10 a.m. Tuesday to 8 p.m. Thursday in the Santa Clarita, San Fernando and San Gabriel valleys and the Santa Monica Mountains.
"Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors," warned an NWS statement, adding that children, seniors and pets must never be left unattended in vehicles, whose interior temperatures can quickly become lethal.
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Partly cloudy skies were forecast in L.A. County Monday closer to the coast along with sunny skies in interior locations and highs of 77 degrees in Avalon; 79 at LAX; 84 on Mount Wilson; 86 in Long Beach; 87 in Downtown L.A.; 94 in San Gabriel, Palmdale and Lancaster; 95 in Pasadena; 96 in Burbank; 97 in Saugus; and 100 in woodland Hills. High temperatures will linger at least through Sunday.