Mother Nature strikes again.
More bad weather was on the way for U.S. travelers as a monster winter storm was expected to pummel much of the nation, bringing a potentially deadly mix of sleet, snow and ice and carving a path from Colorado to New England by week's end.
Storms last week virtually shut down New York's LaGuardia and Kennedy airports for much of the day and stranded travelers in Philadelphia and Washington, D.C. A late-December Northeast blizzard canceled more than 10,000 flights over three days.
The wintry blast descending through the Midwest also is expected to bring subzero wind chill factors to Super Bowl week in Texas. The National Weather Service is advising Packers and Steelers fans to put off travel in advance of the Feb. 6 game in Arlington, Texas, until later in the week. Freezing precipitation and low temperatures in the teens are expected in the Dallas-Fort Worth area Tuesday and Wednesday.
In response to the huge storm, some airlines were allowing air travelers to make changes to their itineraries.
Delta issued an advisory on its website, stating that "winter weather is expected to impact travel to, from and through 20 states in the Northern U.S." through Feb. 4. The airline was allowing travelers to reschedule their itineraries without a fee or get a refund if their flights are canceled or significantly delayed.
United Airlines has issued travel waivers for passengers traveling to, from or through 19 states in the Midwest and Northeast. The waivers permit air travelers to make changes to their itineraries without penalty and get a full refund in the event that their flight is canceled.
American Airlines is waiving change fees for travelers flying to, from or through the 40 Midwest cities.
AirTran Airways is also allowing travelers in affected cities to adjust travel dates through Feb. 10 with no change fees.
On its website, Southwest Airlines posted that is is "keeping a close eye on the conditions" and provided specific information for air travelers in more than 30 cities in the Midwest and East Coast.
Information from The Associated Press is included in this report.