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Chris Sauer shovels snow from her driveway during a winter snow storm in Oregon, Wis., Thursday, Dec. 20, 2012. The first major snowstorm of the season began its slow eastward march across the Midwest early Thursday, creating treacherous driving conditions and threatening to disrupt some of the nation's busiest airports ahead of the holiday weekend.(AP Photo/Wisconsin State Journal,Amber Arnold.)

Chris Sauer shovels snow from her driveway during a winter snow storm in Oregon, Wis., Thursday, Dec. 20, 2012. The first major snowstorm of the season began its slow eastward march across the Midwest early Thursday, creating treacherous driving conditions and threatening to disrupt some of the nation's busiest airports ahead of the holiday weekend.(AP Photo/Wisconsin State Journal,Amber Arnold.)

Winter storms hit U.S.

A winter storm system that blew

through Christmas Day with Gulf Coast tornadoes and snow in the nation's

midsection headed for the Northeast, spreading blizzard conditions that slowed holiday travel all week. The death toll rose to six with car accidents on snow and highways.