Hundreds of flights canceled as winter storm descends upon swaths of the U.S.

For the second time in a week, airlines have grounded hundreds of flights in preparation for a massive winter storm forecast to hit areas from "Texas to New England," CNBC reports. 

Per flight-tracking website FlightAware, over 1,400 U.S. flights were canceled on Wednesday, as well as nearly 1,700 that were scheduled for Thursday, CNBC notes. Airlines such as Southwest, American, Delta, and United "said they would waive fare differences for travelers who plan to rebook flights because of the storm." 

Even Amtrak opted to modify service through the Midwest and the South as a result of the wintry conditions, The New York Times reports. Not that driving, of course, is any better — in Illinois, for example, the state Transportation Department warned of "potential for extremely dangerous and, at times, life-threatening travel" on highways, per the Times.

"The storm will be prolonged, with several rounds of winter weather lasting through Thursday for portions of the central U.S. before shifting to the interior Northeast," the National Weather Service has said, per The Washington Post.

Flooding is also a possibility in the Deep South, notes the Post, as isolated storms forecast for Thursday blow across "southeast Louisiana, southern Mississippi, southwest Alabama and the Florida Panhandle, with a nonzero risk of a tornado." Forecasters are also worried about ice, adds the Times.