DES MOINES, Iowa (AP) -- The first widespread snowstorm of the season is crawling across the Midwest. Whiteout conditions have been stranding holiday travelers and sending drivers sliding over slick roads -- including into a fatal 25-vehicle pileup in Iowa.

State police say drivers on Interstate 35 got into the chain collision about 60 miles north of Des Moines. Officials say two people were killed and seven injured.

The storm made travel difficult from Kansas to Wisconsin, forcing road closures, including a 120-mile stretch of Interstate 35. Sections of Interstate 80 in Nebraska and Interstate 29 in Missouri that had been closed were reopened Thursday afternoon. Iowa and Wisconsin activated National Guard troops to help rescue stranded drivers.

Airlines delayed and canceled hundreds of flights out of Chicago's O'Hare and Midway international airports. Airlines are waiving fees for customers impacted by the storm who want to change their flights. They're monitoring the storm throughout the night to determine if more cancellations would be necessary on Friday.