The fire, which began on Saturday afternoon on the border of Lake and Colusa counties, grew to 2,629 acres on Sunday, an increase of just over 300 acres. Containment remained at 15%.
Cal Fire said 50 structures in the two impacted counties remain under threat.
Firefighters on Sunday worked to construct and tie in control lines around the fire, with a focus on the north perimeter, Cal Fire said.
Officials said they also had bolstered both air and ground resources on the fire Sunday to help keep the fire within its current perimeter.
Still in effect in Lake County are evacuation orders for zones CLO-E070, CLO-E089, CLO-E022 and CLO-E083, with an evacuation warning in place for CLO-E104. Zones can be seen here.
As of noon on Sunday, Highway 20 had been fully reopened east of Clearlake Oaks at Highway 53 in Lake County. The highway had been closed on Saturday.
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