Northern California wildfire explodes overnight to 10,000 acres

A Northern California wildfire more than doubled in size overnight Tuesday, scorching 10,000 acres in Colusa County, according to Cal Fire.

The Sites Fire ignited at about 1:40 p.m. Monday near Sites Lodoga Road and Wilson Creek, southeast of Stonyford, Cal Fire said.

Winds from the north at 10-20 mph and low relative humidity contributed to the fire's rapid spread. A red flag warning is in effect in the area.

The fire is burning out of control, and smoke is drifting south into parts the North Bay, authorities say. The Napa County Sheriff's Office warned residents about heavy smoke in the area.

The cause of the fire is unknown and under investigation, Cal Fire said.

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