By Emily Turner

WINTERS (CBS SF) – Firefighters continue to battle a wildfire in the rugged terrain east of Lake Berryessa on Wednesday evening that has forced evacuations and threatened PG&E transmission lines, authorities said.

Calfire said, as of 6:20 p.m. Wednesday, the blaze had grown to 4,600 acres in a rugged area of grass and oak woodland overnight. Smoke from the blaze caused hazy skies over much of Wine Country. The fire was just 10 percent contained.

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Gusty winds in the area late Tuesday had calmed by early Wednesday, aiding the firefighters in their efforts. But forecasts suggest high winds to come.

The blaze was reported at 4:32 p.m. on Tuesday and has forced the evacuation of the Canyon Creek Campground in Winters and the Golden Bear Estate neighborhood.

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Firefighters were being assisted by eight helicopters, six air tankers and nine bulldozers.

Authorities said the fire was moving toward major power transmission lines running near Highway 128 which was closed from Monticello Dam in Napa County to Pleasants Valley Road in Yolo County early Wednesday.

Yolo-Solano Air Quality Management District is advising residents in Yolo and Solano counties to keep windows closed overnight in case smoke moves in to their areas.

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Also in Northern California, CalFire is battling the Soberanes Fire near Big Sur, which has scorched 46,700 acres and was 27 percent contained as of 6:30 p.m. Wednesday.