Officials remained watchful Saturday for heavy rain that could cause flash flooding due to burned soil erosion from the two wildfires, one near Grapevine and the other in Palm Springs, the U.S. Forest Service's InciWeb reported.
Crews had set up containment lines around 49 percent of the 27,000-acre Mountain fire near Palm Springs and 85 percent of the 700-acre Rancho fire near Grapevine by Saturday night, the Los Angeles Times reported.
Fighting the Mountain fire has required the services of 3,347 personnel, including 68 crews, 228 engines, 11 bulldozers and 20 helicopters, InciWeb reported.
During the first day of the fire, 23 buildings were destroyed, including seven homes, and the total damage cost so far was $18.4 million, InciWeb reported.
The fire's cause was under investigation, InciWeb said.