The County Fire, which started Sunday in rural Yolo County near the community of Guinda, has now consumed more than 88,000 acres.
With 33 percent containment as of 7 p.m. Thursday night, Cal Fire officials are now expecting full containment by Tuesday.
No one has been injured in this grass fire, which started about 10 miles north of Lake Berryessa. But nine structures have been destroyed, and 110 others remain threatened tonight, Cal Fire said.
With temperatures expected to rise into the weekend, conditions should be ripe for the blaze to grow, fire officials said.
Mandatory evacuations remain in effect tonight for residents west of state Highway 16 to Berryessa-Knoxville Road, south of Old County Road 40 and north of County Road 53; and west of Highway 16 to the Yolo/Lake county line, north of Road 40 and south of the Yolo County line.
Berryessa Knoxville Road remains closed from the Pope Creek Bridge to the Napa/Lake county line, as does state Highway 16 between state Highway 20 and Rumsey Hall.