The fire was reported shortly before 4 p.m. with a rapidly building smoke column, Cal Fire and the California Highway Patrol reported.
Cal Fire sent helicopters and air attacks to respond to the fire, which witnesses could see from across the lake in Kelseyville, and from Highway 20 near Blue Lakes.
Ash was reportedly falling near Upper Lake, and light winds were carrying smoke from the fire east along the Northshore.
Reports from the scene indicated that firefighters were having trouble accessing the remote location with their engines.
Initial reports shortly after 4 p.m. put the fire at about 35 acres, but just after 5 p.m. it had reportedly tripled in size.
Cal Fire's Howard Forest Station, which was handling incident command, reported the fire was about 120 acres with a moderate rate of spread at around 5:45 p.m. No structures were threatened at the time.
Efforts to fight the fire included attempting to hold it at a ridge top, fire officials said.
Exact numbers of the dozers, engines and firefighters on scene were not immediately available, but additional resources were being summoned after 6 p.m., including a Konocti Camp strike team, based on radio reports.
The CHP reported that Mill Creek Road at Cow Mountain Road was closed before 5 p.m. due to the fire.
One report from the scene indicated that the fire “will last for days.”
Lake County News will continue to follow the story.
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