DES MOINES, Iowa – The first major snowstorm of the season began its slow eastward march across the Midwest early Thursday, leaving at least three people dead, creating treacherous driving conditions and threatening to disrupt some of the nation's busiest airports ahead of the holiday weekend.

Forecasters warned that heavy snow coupled with strong winds could create blizzard conditions from Kansas to Wisconsin – and guaranteed a white Christmas in some places – after the storm blanketed the Rocky Mountains earlier in the week.

Iowa and Nebraska took a heavy hit from the storm, with nearly a foot of snow in Des Moines and 8.6 inches in Omaha, Neb.