Ahead of the winter storm expected here beginning Friday, airlines announced they will waive ticket change fees and fare differences for customers who want to postpone travel.

American Airlines, which operates 76 percent of flights at Philadelphia International Airport, said passengers flying between Jan. 21 and Jan. 24 can change their tickets, and delay travel as late as Jan. 27 at airports from New Hampshire south to North Carolina and Tennessee.

Delta and United airlines will waive change fees for passengers traveling Jan. 22-24. JetBlue said the waiver will apply to Philadelphia flights only on Saturday Jan. 23. Spirit Airlines said anyone traveling in the Northeast Jan. 22-23 and change their tickets, without a charge. Frontier Airlines said the waiver will apply to flights Jan. 21-24 at airports, including Trenton-Mercer,, and Philadelphia.