Airlines were waiving change fees yet again as a coastal storm threatened airports in the U.S. Northeast for the third time in as many weeks.

The latest weather-related waivers covered Tuesday and Wednesday travel at more than a dozen airports from Pennsylvania through New York and New England.

The details varied by carrier, but they generally allowed eligible customers to make one change to their itineraries without paying a change fee or fare difference.

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Travel dates covered by the waivers also varied by airline; most covered flights on Tuesday and Wednesday, though – so far – some were limited only to flights on Tuesday. Customers should check with their carriers for specific date and airport eligibility.

Airports covered by the waivers as of late Sunday also varied by airline, but included major airports such as Boston, New York JFK, Newark Liberty, New York LaGuardia and Philadelphia. A number of smaller and mid-size airports were covered too, including Albany, N.Y.; Allentown, Pa.; Harrisburg, Pa.; Hartford, Conn.; Manchester, N.H.; Portland, Maine; Providence, R.I.; State College, Pa.; and White Plains/West Chester County, N.Y., among others. 

Regardless of the details of the flexible rebooking policies, fliers traveling to or through the region this week should pay attention to the evolving weather forecasts.

So far, it’s unclear exactly how big of an impact the storm will have on flights. But the previous two coastal storms to hit the region each resulted in the cancellation of more than 3,000 flights and widespread delays.

And at least one airline said it planned to cancel flights ahead of the storm. 

"Winds will not be as operationally limiting as previous winter systems, though the airline will proactively cancel flights in the region due to the heavy snowfall," Delta said in a statement issued late Sunday. "(F)orecast models predict the New York airports to see one to three inches, while Boston will get six to nine inches and Bangor will see upwards of ten inches by Tuesday night."

Scroll down for links to the flexible rebooking policies currently in place at big U.S. carriers. Not all carriers had published policies for the latest storm as of late Sunday. 

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Alaska Airlines/Virgin America

Eligible travel dates: Tuesday and Wednesday (March 13-14)

Airports covered: Boston, New York JFK, New York LaGuardia, Newark Liberty (details)

American

Eligible travel dates: Tuesday and Wednesday (March 13-14)

Airports covered: About 20 from Pennsylvania into New England (details)

Delta

Eligible travel dates: Tuesday and Wednesday (March 13-14)

Airports covered: More than a dozen from Pennsylvania into New England (details)

Frontier 

Eligible travel dates: Tuesday and Wednesday (March 13-14)

Airports covered: New York LaGuardia; Islip/Long Island, N.,Y.; Philadelphia; Providence; Trenton, N.J. (details)

JetBlue

Eligible travel dates: Tuesday (March 13)

Airports covered: Boston; Hartford; New York JFK; New York LaGuardia; Newark Liberty; Newburgh/Stewart, N.Y.; Portland, Maine; Providence; Westchester County/White Plains, N.Y.; and Worcester, Mass. (details)

Southwest    

Eligible travel dates: Tuesday and Wednesday (March 12-14)

Airports covered: 10 airports from Pennsylvania into New England (details)

Spirit

Eligible travel dates: Tuesday (March 13)

Airports covered: Boston, Hartford (details)

United

Eligible travel dates: Tuesday and Wednesday (March 13-14)

Cities covered: More than a dozen from Pennsylvania into New England (details)

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