• Sun. Feb 28th, 2021

L.A.-Area Bobcat Fire Again “Making A Hard Push” For Mt. Wilson Observatory; TV, Radio And Cell Towers Threatened; New Evacuation Orders Issued – Deadline

After days of backfires and dozer lines had held the Bobcat Fire away from the Mt. Wilson Observatory and communications infrastructure there, The U.S. Forest Service reports that the fire “is making a hard push” at Mt. Wilson, and “defensive strategic operations are beginning from Mt. Wilson to the west.”

Every TV station in Los Angeles uses the towers atop Mt. Wilson to transmit its signal. Likewise many radio stations. The peak is also important for ensuring cell phone service in the area.

According to the Angeles National Forest Twitter account, engines, hand crews and aircraft were working on Monday afternoon to snuff out spot fires to the north of Mt. Wilson. The fire was 15% contained as of Monday afternoon, a number that has remained unchanged for at least the past five days.

The Bobcat Fire threatened the mountain last week. It came within 500 feet of the famed observatory and was beaten back. But in the days since low humidity and hazardous winds have allowed the blaze to more than double in size to 105,000 acres on Monday. That makes it one of the biggest fires in L.A. history. The 160,000 acre Station Fire was the largest ever recorded. For a sense of scale, the entire Angeles National Forest is 700,000 acres.

The National Weather Service in Los Angeles warned of “elevated brief critical fire weather” on Monday, with afternoon winds “in the area S-SE 5-10 mph” and relative humidity at 30-35%. Weather-wise, the really bad news is in the extended forecast.

“Wind direction begins to veer to the west and northwest late Wednesday which could be the first evening Sundowners [Santa Anas] returning to western hills of the south Santa Barbara County coast,” says the NWSLA forecast.


Sundowner winds and I-5 corridor winds will likely add downslope warming to many areas with heights building to 592dm or higher by Saturday.

Looking beyond Saturday, the GEFS and ECMWF ensembles both hint at a significant warm up late this weekend and early next week as high pressure encompasses the Great Basin and West Coast. The bottom-line is that we could be flirting with record temperatures once again with highs 95-105 degrees in the coastal and interior valleys, especially if we get any significant offshore wind regime. The hot and dry scenario will likely become a headline not only for the potential heat stress and record highs, but for fire weather concerns for new and existing fires. Large plume growth would likely contribute to rapid fire growth and fire behavior.

The Los Angeles County Sheriff’s Department has issued additional evacuation warnings due to the fire for residents south and west of Upper Big Tujunga Canyon Road; east of Angeles Forest Highway; and north of Angeles Crest (2) Highway.

Structures were damaged in the Antelope Valley over the weekend, according to Vince Pena, unified incident commander with the Los Angeles County Fire Department. The number of homes affected was not available.

On Saturday, the blaze “was very active due to the very windy conditions. The fire reached Juniper Hills and the adjacent communities. Homes were threatened and impacted,” the Forest Service reported. ‘A strategic firing operation occurred to establish a secure line between the Ranch 2 Fire scar and Highway 39. Elsewhere on the fire crews had success improving and securing lines.”

One Twitter user posted video of what he called a “fire-nado” on Big Pines Highway.

The Bobcat Fire erupted on Sept. 6 near the Cogswell Dam and West Fork Day Use area northeast of Mount Wilson and within the Angeles National Forest. The cause remains under investigation.

Full containment of the fire is not expected until Oct. 30.