The big storm heading for the Northeast is already disrupting air travel, with over 2,100 flights cancelled for Friday.
United Airlines said it has cancelled 900 flights for Friday in advance of the storm. Delta Air Lines Inc. cancelled 740. American Airlines was scrapping about 200, according to airline tracking website FlightAware.
New England could get smacked with up to two feet of snow, while New York City is under a blizzard warning for as much as a foot or more.
As of late Thursday, 2,134 Friday flights within, into, or out of the U.S. had been cancelled, according to FlightAware. The airports with the most cancellations are Newark Liberty, New York's LaGuardia and JFK and Boston's Logan International in that order.
On Thursday, the biggest weather problems are in Chicago. O'Hare has seen 108 cancelled departures.
Airlines issued so-called "weather waivers," allowing passengers flying in the storm-affected areas to change their flight date without paying a change fee.
In recent years airlines have tried to get ahead of big storms by cancelling flights in advance rather than crossing their fingers that they could operate in bad weather. Travelers can still face dayslong delays in getting home, but the advanced cancellations generally mean they get more notice and can wait out the storm at home or a hotel, rather than on a cot at the airport.
In addition reservation systems have been programmed to automatically rebook passengers when flights are cancelled. And travellers now receive notifications by email, phone or text message.