LAKE ARROWHEAD -- Cooler weather helped firefighters make strong gains on many of the wildfires burning across Southern California on Saturday, but officials remained guarded about what the rest of the weekend might bring.
Tropical moisture flowing from the south replaced the hot, dry Santa Ana winds that roared in a week earlier and spread fires over more than a half- million acres, destroying more than 2,300 structures, including more than 1,790 homes.
The number of deaths attrib-uted to the fires officially rose to seven. Officials confirmed that the flames killed four suspected illegal immigrants whose charred bodies were found near the U.S.-Mexico border Thursday, said Jose Alvarez, a public information officer for San Diego County emergency services. The victims had not been identified.
By late Saturday, more than a dozen fires were surrounded, and containment of nine other fires ranged from 40 percent to 97 percent. Fire officials in San Bernardino County said they expected a fire there to be fully contained today.
Today's weather forecast, however, predicted another shift.
"We're due for a change, and the weather forecast is going to become warmer and drier," said Chris Caswell with the Orange County Fire Authority.
More than 21,000 structures were considered threatened, and more than 15,000 firefighters were on the lines, the state Office of Emergency Services said.
About 4,400 people remained in 28 shelters in Southern California.
Active fires burned in the Lake Arrowhead resort region of the San Bernardino Mountains, 100 miles east of Los Angeles, and in rugged wilderness above isolated canyon communities of Orange County, southeast of Los Angeles. A big blaze 60 miles northeast of San Diego stopped its advance toward the mountain town of Julian.
Gov. Schwarzenegger on Saturday visited a command post near Orange County's Santiago Canyon fire to announce assistance for people with losses, warn of contracting scams and pledge to find whoever set the nearby blaze that continued to threaten homes after destroying 14.