Massive Winter Storm Slams Upper Midwest

(Dec. 11) -- A dangerous combination of snow, wind and cold is whipping through the upper Midwest, creating full-fledged blizzard conditions in much of the region.

Conditions are so bad in some places that snow plows have been ordered off the road, according to The Associated Press. Some areas got as much as 20 inches of snow.

The powerhouse storm was expected to gain strength as it heads east toward Chicago.

Forecasters say the storm will bring a wintry blast to the Northeast and mid-Atlantic region from Sunday into Monday, ushering in a new shot of Arctic air that will encompass much of the eastern part of the nation next week.

Blizzard watches and warnings were in effect today for parts of South Dakota, Minnesota, Iowa, Wisconsin, Illinois and Nebraska.

The National Weather Service defines a blizzard as "sustained winds or frequent gusts of 35 mph or greater, considerable falling and/or blowing snow reducing visibility frequently to 1/4 mile or less for a period of three hours or more."

The storm is creating near white-out conditions in some areas, resulting in very dangerous travel conditions on highways and delayed flights.

"Life-threatening conditions are expected now through Sunday Morning," the National Weather Service said in an advisory. "Travel is strongly discouraged."

The nasty weather caused trouble for the New York Giants, who are due to play a football game against the Vikings in Minnesota on Sunday. The Giants' plane was diverted to Kansas City today after the harsh weather closed the Minneapolis-St Paul airport. NFL spokesman Greg Aiello said the team is planning to fly to Minnesota on Sunday morning and the game was still on as scheduled at 1 p.m.

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Minneapolis and Green Bay, Wis., were in the path of heaviest snow and wind, which will result in dangerously low wind chills as the storm reaches its peak. Accumulating snow and strong winds will extend southward into Milwaukee, Chicago and Detroit, as well as through the Ohio Valley, where the most severe cold will follow the storm.

The storm will move eastward through Ontario into Quebec on Sunday and Sunday night, but the southern part of the storm will still pack some punch as it moves through the Northeast and mid-Atlantic region.

While the center of the storm will remain to the north, the storm and lake-effect snow immediately following the storm will produce heavy snow in parts of western New York and western Pennsylvania. Mild air racing northward in advance of the storm will likely prevent high snowfall amounts farther to the east, but rain changing to snow might result in slippery road conditions as far east as the major cities along the Eastern Seaboard on Sunday evening.

The storm will be followed by a blast of cold air that will be more intense than the cold that gripped much of the nation last week.

Daytime temperatures will remain below zero in parts of Minnesota on Monday, and below-freezing temperatures are again a threat as far south as central Florida by the middle of next week. The cold air pouring over the relatively warm lakes will result in another multi-day snowstorm in the lee of the Great Lakes. Snowfall totals of 1 to 3 feet are likely in the typically hard-hit snow belt regions, the same general area that had between 1 and 4 feet of snow this week.

Hugh Collins contributed to this report.