WILLITS (CBS SF) — A wildfire that had erupted in the tinder-dry hills north of Willits grew to more than 1,000 acres early Tuesday as local residents were driven from their homes by the advancing flames and officials were forced to shut down Highway 101.

The Oak Fire, burning in the vicinity of Big John Road and 3rd Gate Road north of Willits just west of Highway 101, was first reported around 12:16 p.m. Monday.

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The region was under a National Weather Service Red Flag Warning and at the time the fire began it was 102 degrees with 16 percent humidity. But strong gusty winds predicted for early Tuesday failed to materialize.

Oak Fire Burn Zone / Evacuation Areas Near Willits

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An evacuation center has been set up at the Willits High School. Cal Fire said there was zero containment of the fire and Highway 101 had been shut down north of Willits.

Multiple air tankers and helicopters were assisting ground crews battling the fast-growing blaze.

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The Mendocino Voice posted to their Facebook page a timelapse of the smoke plume rising above Highway 101 taken at around 3:25 p.m.