Airlines have already canceled more than 2,700 Friday flights as they get ready for a storm that threatens to dump up to three feet of snow from New York City to Boston.
Flight-tracking website FlightAware shows 728 cancellations at the three big airports in the New York area. Another 191 flights to or from Boston have been scrubbed, and 137 in Toronto.
Airlines issued so-called "weather waivers," allowing passengers flying in the storm-affected areas to change their flight date without paying a change fee.
Airlines try to get ahead of big storms by canceling flights in advance rather than crossing their fingers that they can operate in bad weather.
At Sky Harbor Airport Friday morning, we didn't see many canceled flights -- the boards had "on time."
What the airlines may not be telling you is that if you have a connecting flight to a city back east, the first leg of your flight may be okay, but you could get stuck there because the second leg may be canceled. Other flights may be re-routed.
As always, the best thing to do is call your airline ahead of time or check online.
The Associated Press contributed to this report.