Road closures, flight delays and power outages abound as a large winter storm barreled across the northern tier of the United States.

A 'bomb cyclone' is intensifying severe winter weather for millions of people across the U.S. The system is expected to knock out power and disrupt holiday travel.

Meteorologists warned NPR that the new storm, coming so soon after the tristate was battered by a separate winter storm over the weekend, could transform into a disastrous ‘bomb

Hamilton County Sheriff Alex Pruismann in Webster City posted on Facebook that there had been numerous accidents on the highway. The Worth County Sheriff's Office reported I-35 also was blocked at the Minnesota border.

More than 40 million are on alert as the next winter storm is forecast to bring inclement weather from the Dakotas into northern New England over the coming days.

The warning from the National Weather Service took effect at 9 a.m. Sunday and was expected to last through 6 a.m. Monday. The NWS predicted that snow accumulations of 3 to 6 inches could fall, swirled by wind speeds of 45 mph. Some areas in the southern valley and west-central Minnesota could see 5 to 7 inches of snow.

A winter storm is set to impact Minnesota, with hazardous travel conditions expected, and a blizzard warning issued for several parts of the state.

The National Weather Service has extended a blizzard warning in Iowa to 18 counties and has issued a winter storm warning for another county.