DES MOINES, Iowa (AP) - The first major snowstorm to hit the Midwest this season is sweeping across the region, shuttering schools and creating dangerous driving conditions.

Forecasters are warning that heavy snowfall coupled with strong winds will create blizzard conditions Thursday from Kansas to Wisconsin.

The weather is also threatening to cause delays at O'Hare International Airport in Chicago, the nation's second-busiest airport, ahead of the busy holiday weekend.

Nebraska's largest school district canceled classes because of heavy overnight snow, as did many districts across Iowa, where drivers are being told to stay off the roads because of whiteout conditions.

The heaviest snow is expected across a swath extending from northwest Missouri into Milwaukee, Chicago and Michigan. As much as a foot of snow could fall in some areas.

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