A storm front that worked its way north through California early this week produced an unusual -- and potentially dangerous -- result: nearly 29,000 lightning strikes in two days, which sparked about 150 fires, Cal Fire officials said Tuesday.
Most of those fires were quickly contained, California Department of Forestry and Fire Protection spokesman Daniel Berlant said, but several were able to grow "fairly quickly" with the help of wind and dangerously dry conditions.
A red-flag warning issued Monday by the National Weather Service for the foothills and mountains of Northern California was expected to be in effect through Wednesday.
Most of the fires were sparked over the weekend in the southern Sierra mountains through Kern County, but Monday night, the storm moved into Northern California.
"We do tend to see in July and August summertime thunderstorms that bring dry lightning," Berlant said.
Still, seeing almost 29,000 lightning strikes from Sunday through Tuesday afternoon was unusual, he said, noting that "every spark has the potential to cause fire."
From Jan. 1 through Saturday -- before the thunderstorm arrived -- Cal Fire had responded to more than 4,700 wildfires that scorched nearly 95,000 acres. Compared with an average 3,300 wildfires each year, Berlant said, that's a nearly 40% increase.
Over the same period last year, a little more than 3,400 wildfires burned about 76,000 acres, he said.
Berlant emphasized that despite the fact that lightning strikes have been at the root of plenty of blazes, humans still cause 94% of wildfires.
"That's the message," he said. "People don't realize that something negligent or stupid that they do can easily cause a fire."
In fiscal year 2012-13, Berlant said, the state spent about $261 million fighting wildfires, of which about $60 million was reimbursed by the Federal Emergency Management Agency.
Since the beginning of this fiscal year, on July 1, the state has spent about $46 million, with $15 million reimbursed by FEMA.