Firefighters battling the Railroad fire near Yosemite National Park relied on cool weather Wednesday to make progress on a blaze that continues to threaten groves of giant sequoias in the Sierra National Forest.
The wildfire is burning between Sugar Pine and Fish Camp. By Wednesday night, it had scorched 11,603 acres and was 43% contained, the U.S. Forest Service reported. Fire officials say moderate temperatures and higher levels of humidity have helped increase containment of the fire, but high temperatures and dry conditions may return Thursday, with the added threat of thunderstorms and spot fires.
"Today is going to be critical," said Cheryl Chipman, a spokeswoman with the forest service. Warmer weather leads to more fires, she said.
Officials say they still fear wet or dry thunderstorms could produce lightning and strong winds that could help spread flames.
The wildfire is burning in areas with dry pine and cedar trees that not only help fuel the blaze but also increase the risk for firefighters.
The fire has burned 14 structures and forced the evacuations of several mountain communities. Roughly 600 residents have been affected, Chipman said.
More than 800 personnel are fighting the fire, including 14 hand crews, six helicopters, 89 engines and 14 bulldozers. Air tankers have been ordered to help support firefighting efforts.
The fire broke out Aug. 29 near Yosemite Mountain Sugar Pine Railroad, just north of Oakhurst.
The fire has forced mandatory evacuations for several campgrounds, lodges and mountain communities. The California Highway Patrol blocked access to Highway 41 from south of Wawona to Sky Ranch Road.
On Tuesday, the fire had moved into the Nelder Grove, home to more than 100 mature giant sequoias. The fire did not damage the trees, but it burned the vegetation beneath them.
Chipman said firefighters were focusing their efforts on protecting structures and conducting more fire operations to slow the spread of the fire. Fire officials say the fire will continue east toward Little Sandy — and downslope from the Speckerman Mountain peak — and southwest toward Sugar Pine and Cedar Valley.
In California, there are more than 20 active fires, including the La Tuna fire in the city of Los Angeles, which has burned 7,194 acres and is 80% contained.
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8:05 p.m.: This article was updated with new acreage and containment figures.