"This is pretty serious," Weaver said. "Some of these areas have not burned in over 40 years."
Smoke and fire billowed near neighborhoods on the outskirts of Sierra Madre near Bailey Canyon Wilderness Park. The fire moved slowly as it fed on brush and was estimated to be 5 to 10 percent contained. It is expected to continue burning for another two or three days.
Winds were calm early Sunday, boosting firefighter efforts, Weaver said.
Helicopters made water drops Sunday morning on a steep ridge above Sierra Madre, about 15 miles northeast of Los Angeles and just east of Pasadena. A fixed-wing water tanker also made at least one drop of flame retardant.
The blaze also stranded 50 guests from a wedding party at the Chantry Flats ranger's station on Saturday until they were airlifted out Sunday afternoon, Weaver said. It took five helicopter trips from the ranger's station to the parking area where the wedding party's cars were. The party then was escorted out by road.
The fire was first reported Saturday afternoon in a wooded area a few miles northeast of Pasadena. It was windy at the time and unseasonably hot, with temperatures approaching 100 degrees.
The flames also brought the evacuation of a Boy Scout camp Saturday and left about 100 hikers stranded in a parking lot. Most of the Scouts had already left the camp by the time the evacuation was ordered, Weaver said, and no injuries were reported.
Firefighters originally had hoped to have the blaze contained Sunday, but gusting winds late Saturday night kept the fire out of control and sent it creeping toward nearby homes. The mandatory home evacuations came shortly before 11 p.m.
Two shelters have been set up for evacuees.
Flames outlined steep ridges about a mile above Sierra Madre, a San Gabriel Mountains foothill community of about 11,000 popular with artists.
To the south in San Diego County, about 40 acres burned in thick brush about 15 miles north of downtown San Diego. No injuries or property damage had been reported, a San Diego Fire Department spokeswoman said.
Homes in the following areas are being evacuated:
Oak Crest Drive north of Carter Avenue
North of Carter Avenue East to Mira Monte Avenue to Mountain Trail
Sierra Madre Lower and Upper Canyons
All areas North of Grand View Avenue from Mountain Trail east to Santa Anita Avenue
Evacuation shelters have been set up at:
222 W. Sierra Madre Blvd.
170 W. Sierra Madre Blvd.