Firefighters from Lakeport, Northshore and Kelseyville pounced on the blaze, blunting its progress. A quick response by Cal Fire air tankers and helicopters prevented the fire from jumping Highway 20.
Evacuations were called for in the Mockingbird Lane area for a time, with law enforcement officers going door to door to notify residents.
The fire tried to jump west of the highway at one point until an air strike knocked it down in that area. The shifting winds kept the fire on the east side.
The ignition point appeared to be just south of the road leading to the Upper Lake PG&E substation. It was very close to the roadway. At last report the fire had burned 20 acres and crews had stopped its progress and were mopping up hot spots.