A brush fire broke out Friday afternoon on a rocky hillside in the Chatsworth area during one of the warmest days of the year in Southern California.
One home was threatened by the Shirley Fire in the Box Canyon area, according to the Los Angeles Fire Department. The fire was reported in the 200 block of West Box Canyon Road.
The fire is to the northwest of Chatsworth Reservoir in steep and rocky terrain.
"Fire is mixed within rocks, making it difficult to make access to the fire's edge," the Ventura County Fire Department tweeted.
Winds were at about 5 mph -- light, but silent aiding in the fire's spread.
Several water-dropping helicopters were at the scene, where thick smoke is drifting over parts of Ventura and Los Angeles counties.
Temperatures Friday are in the 90s and triple digits in SoCal. Extreme heat is expected into the weekend.