Airlines have canceled more than 700 Boston flights scheduled for Tuesday ahead of another strong winter storm that's threatening to dump more than a foot of snow in parts of the region.

About three-quarters, or nearly 400 flights across several airlines from Boston are canceled Tuesday, according to flight-tracking site FlightAware. A further 321, or about 60 percent of flights to the airport are also canceled.

American Airlines canceled its entire Boston schedule for Tuesday and warned of the potential for other flight cancellations around the Northeast. The airline had 89 departures and an equal number of arrivals scheduled from Boston's Logan International Airport on Tuesday, American Airlines spokesman Ross Feinstein said.

American's cancellations include its hourly shuttle service between Boston and New York's LaGuardia. Delta has canceled most of its Boston-LaGuardia shuttle service for Tuesday.

Airlines including American, Delta and JetBlue, are waiving ticket-change fees for travelers affected by the storm. Southwest said passengers won't pay additional fees for a date change. The airline doesn't charge date-change fees but passengers generally have to pay more if the fare is higher on the new travel date.

Airlines will often cancel flights ahead of time to avoid stranding passengers and crews, which can lead to further delays if employees are not in place to work when flights resume.

A nor'easter last week prompted airlines to call off more than 2,400 flights.