A major snowstorm in the Midwest and Great Lakes is bringing winter to some Thanksgiving travelers with forecasters saying the northeast U.S. could get its own early winter storm next week.

Winter storm warnings and advisories extended from Montana to Ohio, the National Weather Service said.

Forecasters warned there could be airport delays and slowed traffic as the snow could be falling at more than an inch (2.5 centimeters) per hour in some areas.

The storm already dumped more than 8 inches (20 centimeters) of snow on northern Iowa by Saturday morning and at least that much snow was expected in Chicago as well as other parts of Illinois, Wisconsin, Indiana and Michigan.

Airports in Chicago and St. Louis reported delays of about an hour Saturday morning, according to FlightAware.com, as one of the busiest travel days cranked up after Thanksgiving.

Snow-covered roads and slow travel were reported all across Iowa and northern Illinois and Indiana.