A large grass fire west of Fairfield that threatened more than 60 homes was one of hundreds throughout the northern part of the state Sunday that kept fire crews busy and filled much of the sky with a smoky haze.
The blaze in Solano County, which broke out Saturday about 40 miles southwest of Sacramento, was 35 percent contained by Sunday night. It had scorched 3,500 acres, destroyed one home and threatened more than 100 buildings, according to the state Department of Forestry and Fire Protection.
While the cause of the blaze was unknown, at least 700 other fires in Northern California were sparked by a series of lightning storms over the weekend, authorities said. The fires consumed a combined 10,000 acres.
In most years, lightning strikes cause small fires that burn out before spreading, officials said. But with record-dry conditions this year, the strikes led to fires ranging from a half-acre to 500 acres.
"It seems that every decade we'll get one of these storms to move in and cause these lightning strikes," said Cal Fire spokesman Daniel Berlant. "But this year because the conditions are so dry, you get just a little wind, high temperatures and low humidity and it's off to the races."
About 90 firefighters battled the Fairfield fire, the largest fire to break out in Northern California over the weekend.
Smoke shrouded the vineyards near Green Valley, midway between Napa and Fairfield. The fire prompted mandatory evacuations for dozens of residents.
"We're trying to get together the essential things," said Robin Cox, who was helping her mother, Margaret Copner, get ready to leave her home off Green Valley Road.
The family was packing photographs and live chickens into a Honda Civic already cramped with clothing.
"These things can be replaced, but some of the family photos are irreplaceable," Cox said.
On Twin Sisters Road, Marilyn and John Roscoe had ignored a mandatory evacuation order Saturday night, deciding to defend their home from the flames. As they hosed down the house, a wall of flames reached to within feet of the home and took out two barns.
"We didn't leave, we wouldn't leave," Marilyn Roscoe said.
Russ Rasmussen, a captain with the Petaluma Fire Department, said when residents do not obey orders to leave they can pose a problem to the evacuation effort.
"When officials decide to evacuate an area, we usually do it with enough advance notice, but that's usually a narrow window," he said.
A handful of smaller fires in the region burned in more remote areas, including the wooded hills of Placer County.
One fire broke out late Saturday near Mosquito Ridge Road, just south of Michigan Bluff and about five miles east of Foresthill, said Cal Fire spokeswoman Joann Cartoscelli. The fire was believed to have been sparked by a lightning strike, Cartoscelli said.
"We'll get lightning, but usually it comes with precipitation," Cartoscelli said.
The fire had consumed about 55 acres of steep ravines by Sunday afternoon but was not threatening any homes.
Another fire broke out about 2 p.m. Sunday on Ravine Court near Newcastle. That fire was nearly contained a few hours later, Cartoscelli said.
Further south, a fire burning west of Morgan Hill and Gilroy forced several residents from their homes Sunday, though officials did not have exact evacuation figures. A lightning strike Saturday afternoon was blamed for the blaze, which had burned nearly 2 square miles and was 10 percent contained.
Meanwhile, firefighters worked against rising temperatures and falling humidity in the remote mountain forests blanketing the state's northernmost counties to keep hundreds of small blazes from expanding.
"Our concern is how many of them are going to break out?" said Cal Fire's Roy Del Carlo.
Storms were responsible for as many as 75 fires in Shasta-Trinity National Forest, near Redding. Those fires ranged in size from less than an acre to more than 750 acres. None immediately threatened homes, according to the U.S. Forest Service.
An additional 90 fires ranging in size from one acre to 125 acres burned in the Mendocino County area alone, Cal Fire officials said.
In Santa Cruz County, the Trabing fire was expected to be fully surrounded Sunday evening. Roughly 2,000 people had fled their homes Friday, but by Saturday the evacuation orders had been lifted.
Officials had expected full containment on Saturday, but hot weather and new fires kept fire crews in the area busy. By Sunday nightfall, it had charred 630 acres, or less than a square mile, and destroyed 10 homes along with 10 other buildings.
The cause of the Trabing fire is under investigation.
It was the third major blaze to hit Santa Cruz County in the past month.
To the south along the coast, firefighters worked against a nearly 83-square-mile fire in a remote part of the Los Padres National Forest in Monterey County. It was about 59 percent contained.
Wildfires have destroyed at least 125 homes in Northern California in 2008. Destructive blazes began breaking out in the region just as California's unofficial fire season got under way in mid-May following one of the state's driest periods on record.
As of 10 p.m. Sunday, much of the Sacramento region was experiencing air quality that was unhealthy for sensitive groups. The closer to the Solano County blaze, the worse the air quality was.
The Sacramento Metropolitan Air Quality Management District recommends that persons stay indoors as much as possible when smoke can be detected in the air to avoid its particulate matter.
Call The Bee's Ryan Lillis, (916) 321-1085. The Associated Press contributed to this report.
