Crews battling wildfires that may have cost one life, burned 58 homes and 75,000 acres of desert faced a chance of thunderstorms Sunday — and with it, lightning that could start new blazes or rain that could flood the denuded canyonlands.

"We're definitely concerned," California Department of Forestry spokeswoman Karen Guillemin said.

The National Weather Service said there was about a 30 percent chance of storms in the Southern California region, where nearly 4,000 firefighters were struggling to surround the combined Sawtooth and Millard fires before they ran up into mountain resort towns where thousands live.

On Saturday, searchers found the body of a man who had been missing since the Sawtooth fire burned through historic Pioneertown, California, on Tuesday.

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The body of Gerald Guthrie, 57, was found shortly after 11 a.m., said Cindy Beavers of the San Bernardino County Sheriff's Department.

His body was found in a charred area at the base of a small hill less than a half-mile from his two-story domed home, which escaped the flames that destroyed desert scrub and Joshua trees all around.

A family member last heard from Guthrie when he called from his 10-acre property and said the fire was close and he was preparing to evacuate, authorities said.

The cause of his death remained under investigation but sheriff's Detective James Porter said it appeared to have been fire-related.

With humidity higher and temperatures slightly lower, fire officials reported some progress on the fires, which covered areas equal to more than 110 square miles in the inland region about 100 miles east of Los Angeles.

The 62,000-acre Sawtooth Fire was 60 percent contained — its eastern flank no longer a problem but its western side still a major concern.

A mandatory evacuation remained in effect for one small canyon but was lifted in several others areas. Ignited by lightning a week ago, it roared to life a few days later, destroying 58 desert houses and mobile homes and many outbuildings.

Fire officials estimated damage from the fire at more than $8.4 million and firefighting costs at $10.3 million.

The adjacent Millard complex of fires, which merged with the Sawtooth on Friday, grew to 15,572 acres and was 10 percent contained. Crews protected a handful of homes in a canyon, but there were no evacuations.

The fires burned into the San Bernardino National Forest but as of Saturday were not considered immediate threats to communities in the Big Bear Lake region atop the range.

Governor Arnold Schwarzenegger toured the area by helicopter on Saturday and visited a command post at Yucca Valley High School with his wife, Maria Shriver.

"It is a huge fire. It is really extraordinary how quickly it has spread out," he said. "And that's why I say it is very dangerous and they have to contain it as quickly as possible."

Elsewhere in Southern California, a 500-acre blaze in Redlands was 100 percent contained after destroying one building. It broke out Friday night and initially threatened 100 homes.

In San Diego County, lightning apparently sparked a 260-acre wildfire about 10 miles east of the town of Julian, California.

The fire, which erupted shortly after 4 p.m. Saturday, was 100 percent contained and did not threaten any buildings, CDF spokeswoman Roxanne Provaznik said.