Storm forecast to bring wild weather to Calif., central U.S.

A large winter storm is forecast to bring heavy snow and dangerous travel conditions to the West this weekend before barreling toward the central U.S.

As the storm heads toward the Plains, it may trigger severe thunderstorms and possibly a tornado outbreak in the country's midsection next week, while blizzard conditions may continue on the storm's cold sides to the north and west, according to AccuWeather.

"You name it, this storm will bring it in terms of wild weather next week," said AccuWeather meteorologist Bernie Rayno.

Winter storm warnings were issued Saturday across much of the West, including parts of Washington, Oregon, Idaho, northern California and Nevada.

Meanwhile, millions in Southern California were bracing for a weekend of rain, high winds or snow at higher elevations.

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Winter storm to hit western US

Between Saturday and Monday, a large winter storm is expected to expand across the West, unloading feet of snow in the Sierra, producing high winds and making travel dangerous, especially across mountain passes, according to the National Weather Service.

These conditions will continue in California over the weekend before spreading east, the weather service said.

On Saturday, up to six inches of snow were falling per hour in some parts of the Sierra Nevada, the California Department of Transportation said on Twitter.

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Mountain roads were covered in snow, the weather service said on Twitter. It spurred multiple vehicles to spin out along northern California's Interstate 80, according to the state transportation department.

The Sierra Nevada may see snow accumulations of more than 5 feet through Sunday.

Saturday morning more than 30,000 people were without power in the Sacramento area and winds gusts could still bring down tree branches and power lines, forecasters warned.

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The Forest Service Sierra Avalanche Center issued a backcountry avalanche watch late Friday through Saturday morning, warning of "very dangerous avalanche conditions." The center warned the storm is forecast to bring blizzard conditions, high snowfall rates and gale-force winds.

Flood watches in multiple California counties

Multiple flood advisories and flood watches where in effect throughout California Saturday, including a flash flood watch affecting Los Angeles County through the evening. 

There was also a flash flood warning affecting Monterey County, an area in central California that includes Big Sur, with the possibility of "rain rates of up to 1 inch per hour" through late Saturday, the weather service said.

In Santa Cruz, California, flooding on highways, streets andunderpasses was possible, the weather service said on Twitter.

Thunderstorms, tornadoes possible as storm heads to central US

On the storm's warm side, unstable air may bring severe weather. The National Weather Service's Storm Prediction Center forecasts Monday and Tuesday as dangerous thunderstorm days.

The central U.S. is expected to be hit worst by severe weather from Monday to Tuesday as forecasters warn of a potential tornado outbreak, according to AccuWeather.

"A significant risk to lives and property will unfold as thunderstorms erupt, become severe and likely unleash multiple tornadoes," AccuWeather said.

The National Weather Service also said these thunderstorms may bring "all hazards, including tornadoes, damaging winds and hail."

The storm may also increase the risk of flooding in the Tennessee Valley as scattered weekend thunderstorms from central Texas to Tennessee ramp up Monday from Texas to Oklahoma, according to AccuWeather.

Around Tuesday, severe weather and tornado threats are expected to expand east, bringing the the possibility of tornadoes, hail, high winds and torrential downpours to areas from northeastern Texas and eastern Oklahoma to the Mississippi river, AccuWeather forecast.

Contributing: Associated Press

This article originally appeared on USA TODAY: Winter storm in weekend weather forecast; storms in central US next