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REDDING, Calif. (AP) — Firefighters battling deadly and destructive wildfires in Northern California faced worsening weather conditions on Friday.
The National Weather Service issued warnings for critical fire weather conditions into Saturday, saying a series of dry low-pressure systems passing through the region would bring afternoon gusts up to 35 mph (56 kph).
According to ABC10's Rob Carlmark, even though Northern California is "cooling" to the low 90's this weekend, existing fires will threaten containment lines.
"The big concern is that any new fires that break out will grow quickly and it will strain already maxed out resources," Carlmark said. "Some calls for resources have gone unfilled because equipment or crew was not available. This also happens to be a weekend when people tend to be out and about doing things. More outdoor activities can create more opportunities for accidental fire starts."
Photos: Wildfires of Northern California
Common ways people accidently start fires are by using yard work equipment like lawn mowers that kick up rocks and sparks. Gas powered weed whackers can get hot and when set down can start an accidental fire. Trimmers and chainsaws can also get hot and start fires or create sparks. The large Zaca fire was starting by welding in a shed. Driving a car through thick grass can start a fire from underneath the car. Cigarette smoking in a dry area has caused many fires over the state. Campfires that re-ignite can be a big issue especially morning fires that flare up in the afternoon wind. Also target shooting can create a spark that will cause a fire.
A red flag warning goes into effect from 11 a.m. Friday, Aug. 3, and lasts through 10 p.m. Saturday, Aug. 4.
Forecasters said the highest threat areas included the so-called Carr Fire near the city of Redding and the Mendocino Complex of two fires north of San Francisco. The forecast included extremely low humidity levels that leave vegetation ready to burn.
The 206-square-mile (533-square-kilometer) Carr Fire 100 miles south of the Oregon border was 39 percent contained after destroying 1,060 homes and many other structures.
Two firefighters and four other people have been killed since the blaze, which ignited July 23, raced with extraordinary fury toward the region's largest city. More than 1,300 homes remained threatened.
To the southwest, new evacuations were ordered late Thursday at the Mendocino Complex, where the so-called Ranch and River fires have ravaged a combined 240 square miles (621 square kilometers), destroyed 41 residences and threatened 9,200 homes.
Both fires were active overnight, including a rapid expansion eastward by the Ranch Fire. Combined containment was 30 percent early Friday.
In the Sierra Nevada, firefighters achieved 41 percent containment of a 115-square-mile (298-square-kilometer) forest fire that has shut down Yosemite Valley and other adjacent portions of Yosemite National Park at what is normally the height of summer tourism.
Two firefighters have been killed there since a fire erupted just west of Yosemite in the Sierra National Forest.
New evacuations were ordered late Thursday at the Mendocino Complex.