Strong, gusty offshore winds will whip across the Southland today amid low humidity, bone-dry vegetation and unseasonably high temperature, creating wildfire conditions, forecasters said.
A fire weather watch, which means that conditions conducive to critical fire weather are expected, will be in force in Los Angeles and Ventura counties from late tonight through Thursday evening, said a National Weather Service advisory.
Forecasters predicted northeast winds of between 20 and 30 miles per hour gusting to between 40 and 45 mph along the coast and in lower valleys tonight, with gusts of between 50 and 55 mph in higher valleys and in the mountains into Thursday evening.
In Los Angeles County, the fire weather watch applied to wide areas — the coast, metropolitan L.A., the downtown area, the Hollywood Hills, the Santa Monica Mountains Recreational Area, the San Gabriel Mountains, the Angeles National Forest, and the San Fernando, Santa Clarita and San Gabriel valleys.
An NWS advisory cited a “high likelihood for hazardous fire behavior” from late tonight through Thursday, with humidity levels vacillating between the low teens and single digits and the vegetation becoming dangerously dry between Wednesday morning and Thursday.
The heat also will be a factor, generated by what the advisory called “an unseasonably warm air mass” developing today, “with additional warming and near-record high temperatures expected for Wednesday and Thursday,” when highs of 100 degrees Fahrenheit are possible in L.A. and Ventura counties.
In such conditions, “extreme fire behavior is possible if fire ignition occurs.”
A high wind warning — signifying an expectation of 58 mph or greater — will be in force until 3 p.m. Wednesday in the Santa Clarita Valley and the Santa Monica and San Gabriel Mountains.
A less serious wind advisory will be in effect until 3 p.m. Wednesday in the San Fernando Valley, the coast, Metropolitan Los Angeles and downtown L.A.
The winds could wreak havoc with traffic, forecasters said. They said strong winds may disrupt traffic on Interstate 5, the Antelope Valley (14) Freeway, Pacific Coast Highway in the Malibu and Pacific Palisades areas, the San Diego (405) Freeway through the Sepulveda Pass. The drivers of high-profile vehicles were urged to use caution.
The NWS forecast sunny skies and unseasonably hot temperatures, with highs of 74 on Mount Wilson; 80 in Palmdale and Lancaster; 81 in Avalon; 84 at LAX; 89 in Saugus; 92 in Newport Beach; 93 in downtown L.A.; 94 in Pasadena and Burbank; 95 in Long Beach and Woodland Hills; and 97 in Anaheim.
Temperatures will climb a few degrees over the coming days.