The Walker Fire burning in Plumas National Forest saw “increased fire behavior” overnight after mild conditions Wednesday, pushing the wildfire to nearly 50,000 acres Thursday morning, according to the U.S. Forest Service.

Growth has still slowed significantly compared with last week, and containment of the blaze is steadily increasing as a total of nearly 2,000 fire personnel are assigned to the fire. After sparking Sept. 4, the Walker Fire is now reported at 49,272 acres and is 28 percent contained, the Forest Service said in a Thursday morning update.

Mandatory evacuation orders are still in effect for the Murdock Crossing and Stony Ridge areas, but warnings have been reduced to evacuation advisories in all other affected areas by the Plumas County Sheriff’s Office. Some roadways remain closed, but Highway 395 is fully open to traffic.

The Walker Fire is burning in the Genesee Valley about 11 miles east of Taylorsville. A thunderstorm brought rain and high humidity to the area at the beginning of the week, but the latest Forest Service incident report says fire crews anticipate increased fire activity Thursday as fuels dry out and the weather warms.

As 1,891 personnel remain assigned to the Walker Fire, the Forest Service advises that increased vehicle and equipment traffic may cause delays in eastern Plumas County.

The wildfire remains California’s largest so far of 2019. Its official cause remains under investigation.