The Bobcat Fire Sunday remains at only 6% contained, burning 31,991 acres, authorities said.
The blaze continues to burn downhill toward Monrovia and north toward State Route 2 in the Buckhorn Area, with “significant” western growth towards Mt. Wilson, Angeles National Forest officials reported.
A smoke advisory remains in effect through Monday in most of Los Angeles County and parts of Orange, Riverside and San Bernardino counties.
“Fire crews will continue to focus on increasing containment lines along the south end of the fire to protect the foothill communities,” officials said Saturday. “Local fire departments will continue to conduct structure protection within the foothill communities.”
On the northeast edge of the wildfire, crews used strategic firing operations to contain the fire south of Highway 2 and west of Highway 39, as hoped, according to Angeles National Forest officials.
However, fire activity on the southern front, which reached Santa Anita Canyon near Chantry Flat, is expected to remain high throughout the night.
The Bobcat Fire, which erupted midday on Sunday, Sept. 6 near the Cogswell Dam and West Fork Day Use area, prompted evacuation warnings in seven San Gabriel Valley foothill communities and was not expected to be fully contained until Oct. 15.
Firefighters had been working around the clock to hold the fire just above West Fork on Highway 39 while strengthening containment lines and slowing progress of the flames moving farther south toward foothill communities, according to the U.S. Forest Service.
“The eastern portion of the fire was burning downhill and entering into a burn scar from the Ranch2 Fire, creating less intense fire behavior for firefighters. Much of the western side of the fire was entering an old burn scar as well, which reduces the rate of spread,” firefighting officials said.
The Ranch 2 Fire broke out Aug. 13 near Azusa and has burned 4,237 acres. It was at 93% containment this weekend.
“The recent Ranch 2 Fire, Fish Fire and the 2009 Station Fire are helping to slow fire progression, however the Bobcat Fire continues to burn north and east where there is no fire history in the last 80 years and in the San Gabriel Wilderness,” the Forest Service said.
The most activity was in the north and south ends of the fire, the U.S. Forest Service said.
Evacuation warnings remain in effect in the foothill communities of Duarte, Bradbury, Monrovia, Sierra Madre, Pasadena, Altadena and Arcadia.
An evacuation order was also issued for Camp Williams.
Angeles Crest Highway 2 was closed from Upper Big Tujunga Canyon Road to Big Pines, Highway 39 was closed at Old San Gabriel Canyon Road, and Glendora Ridge Road, Glendora Mountain Road, and Mount Wilson Road were closed.
Smoke and ash were expected in portions of Los Angeles, San Bernardino, Riverside and Orange counties, and unhealthy or worse Air Quality Index levels due to particulate matter concentrations are possible in areas of direct smoke impacts through Sunday, according to the South Coast Air Quality Management District.
Los Angeles County health officials announced that some COVID-19 testing centers would be closed this weekend due to health concerns stemming from the unhealthy air quality.
Testing sites at East L.A. College in Monterey Park, the Pomona Fairplex and San Gabriel Valley Airport in El Monte were closed Saturday and Sunday, while the site at College of the Canyons in Santa Clarita will be closed Sunday.
Officials with the Los Angeles Zoo said Saturday that the zoo would be closed Sunday and Monday due to the unhealthy air.
“The Zoo hopes to reopen on Tuesday, Sept. 15, but we will continue to monitor air quality advisories issued by the South Coast Air Quality Management District and adhere to air quality safety guidance for safely reopening,” officials said.
They added that staff was closely monitoring the animals who reside in outdoor habitats, but based on past fire events in the Los Angeles area, they did not anticipate any air quality issues to affect the animals.