The wildfire burning in Riverside County has now expanded to 11,000 acres and is only 10% contained, fire officials said Thursday.
The cause of the Silver fire, which is burning near Banning, remains under investigation.
Julie Hutchinson, a battalion chief for the California Department of Forestry and Fire Protection, said she had just left a meeting with her fellow firefighters in San Bernardino when she noticed the smoke Wednesday afternoon.
"We could clearly see the column developing," she said. "It just continued to get larger and larger."
Hutchinson estimates she got to the Silver Fire within the first hour it broke out. Within two hours, the flames had split to a northern and southern face and were running east toward Twin Pines Ranch in the San Jacinto Mountains.
Only two roads leave Twin Pines Ranch -- one southbound toward Highway 243, the other north toward the 10 -- and both were inaccessible because of the fire.
"This fire yesterday had a whole lot of open line as it was moving across from the west to the east," Hutchinson said. "It went into the community very quickly. That right there was challenging because the fire moved so rapidly."
One resident had to be airlifted to a hospital after being burned "head to toe," Hutchinson told KTLA. The condition of the victim could not immediately be determined.
"As we were starting to bring the equipment, the fire had already made runs off the flats and toward the communities in the San Jacinto Mountains," CalFire spokesman Daniel Berlant said. "We had a lot of resources thrown on this fire early, but it was still a very fast-moving fire."
One thing is clear: A confluence of factors, including tinder-dry conditions and steady winds, combined to create a monster of a fire in short order -- one that at last count had destroyed or damaged at least 15 structures and claimed scores of pets.
"This is a different side of San Jacinto Mountains," Berlant said. "This fire has definitely grown a lot faster than the one last month, in general."
In that blaze, the Mountain fire, more than 27,000 acres of chaparral and timber were scorched near Idyllwild, and multiple buildings -- including mobile homes, a commercial building and several outbuildings -- were destroyed.
Firefighters were able to finally get a handle on the fire after cooler and wetter-than-normal conditions gave them a break.
In the case of the Silver fire, inaccessible rugged terrain, dry conditions and steady winds have combined to make its spread relentless, officials said.
According to CalFire Deputy Director Janet Upton, it's a worsening trend.
The fires this year have been noticeably more intense since May, she said, noting that 11 of California's 20 worst fires in history have been in the last 10 years.
According to CalFire, roughly 80,000 acres across the state have burned so far this year. At the same time last year, that number was 39,386.
"The intensity isn't being caused by winds, they're caused by fuel," Upton said. "They're causing fire behavior to be extreme."