Heavy Snow Targets Chicago and Other Cities

Nov. 30, 2006 — -- The window is closing for travelers trying to beat the storm bearing down on the nation's mid-section. Two major airlines have announced extensive flight cancellations starting tonight at Chicago's O'Hare Airport.

An American Airlines spokesperson tells ABC News it will halt 50 percent of its flight operations at 10 pm and does not plan to resume flights until noon on Friday.

United Airlines also announced cancellations of all domestic flights departing from O'Hare on Friday from 6 am to noon. The cancellations by both airlines combined total more than 700 flights out of one of the nation's busiest airports.

The storm targeting Chicago is packing high winds and heavy snow. As many as 10 inches may fall overnight, according to the National Weather Service.

Earlier today, nasty winter weather stretching from Michigan to Texas prompted American Airlines to cancel all flights out of St. Louis and about 35 percent of its flights out of Dallas/Ft. Worth.

But it isn't only air travel that's being snarled: Freezing rain and sleet precedes the snow and has already made for treacherous driving conditions through the Midwest. Police in St. Louis are telling residents not to travel unless it is absolutely necessary.