So far this year, California fire officials have battled 4,300 wildfires a stark increase from the yearly average of nearly 3,000 they faced between 2008 and 2012, said Daniel Berlant, a spokesman for the California Department of Forestry and Fire Protection.
Those fires have already burned more than 71,000 acres, while the annual average for acreage charred in the last five years was 113,000, he said.
"We have seen a significant increase in our fire activity, and much earlier than normal," said Berlant, adding that fire season began in mid-April, about a month ahead of schedule. "We're not even yet into the time period where we see the largest number of damaging fires."
U.S. Sen. Barbara Boxer, D-Calif., who lives in Riverside County, said more than 165,000 acres have burned in California this year and climate change is setting conditions for more disastrous blazes, while budget cuts are limiting resources to fight them.
This year, state fire officials have called up more firefighters and reserve engines on days with hot, dry conditions to prepare for possible wildfires, Berlant said.
And while officials encourage residents to rid their properties of dry brush before fire season starts, authorities are now urging the public not to use lawnmowers or weed eaters during the heat of the day since a spark off the metal blades can trigger a blaze, he said.
To date, the so-called Silver Fire burning 90 miles east of Los Angeles has forced some 1,800 people to flee their homes. The fire grew by 2,000 acres to 25 square miles overnight but it was significantly less active Friday morning.
Six people have been injured, including a civilian with serious burns and five firefighters. Evacuation orders were issued for Cabazon and the rural communities of Poppet Flats, Twin Pines, Edna Valley and Vista Grande, and several camping and hiking areas.
In the Twin Pines neighborhood outside Banning, Andy Schrader said he couldn't get out in time. The wildfire crept up suddenly and blew over his house, burning his motor home and singeing his hair as he sprayed water from a hose try to keep the house wet.
"I could feel my face burning," the 74-year-old carpenter said. "And I thought I was going to die."
Most of Southern California's severe wildfires are associated with Santa Ana winds caused by high pressure over the West that sends a clockwise flow of air rushing down into the region.
This week's fire, however, was being fanned by a counter-clockwise flow around a low pressure area over northwest California. The National Weather Service said conditions could change in the second half of next week, with weaker winds in the mountains and deserts.
It was the second major wildfire in the San Jacinto Mountains this summer. A blaze that erupted in mid-July spread over 43 square miles on peaks above Palm Springs, burned seven homes and forced 6,000 people out of Idyllwild and neighboring towns.
The latest fire also burned in the footprint of the notorious Esperanza Fire, a 2006, wind-driven inferno that overran a U.S. Forest Service engine crew. All five crew members died. A man was convicted of setting the fire and sentenced to death.
A different blaze, a 60-acre wildfire, forced evacuations of about 75 homes Thursday near Wrightwood, a community in the San Gabriel Mountains popular with skiers located about 40 miles northeast of downtown Los Angeles.
Wildfire experts say the traditional fire season has grown longer in California as rainfall has been lower than usual over the last two years and tapered off sooner.
Tom Scott, a natural resources specialist who teaches at University of California campuses in Riverside and Berkeley, said plants can have a harder time staying hydrated under such conditions.
"The whole system is like a bank account it's being drawn down," he said.
Richard A. Minnich, a professor of earth sciences at University of California, Riverside, said much of Southern California is in pretty good shape because older vegetation burned off during a spate of wildfires over the last decade, but there are spots at serious risk because of the prevalence of old-growth chaparral.
"Wherever there is very old chaparral, we've got a tremendous threat," he said.