A Delta flight on a slushy runway at John F. Kennedy International Airport in New York on Sunday. (Kathy Willens/Associated Press)

Air travelers hoping to fly on Monday are encountering yet another day filled with cancellations and delays, as the winter storm that snarled travel last week is being followed by dangerously brutal cold in much of the United States.

There have been more than 3,700 flights canceled and another 5,600 delayed as of 4:30 p.m. on Monday, according to FlightAware. Chicago, where heavy and persistent snow has been a problem since New Year’s Eve, is seeing some of the worst headaches in the country, with more than 1,500 flights traveling through O’Hare International Airport already canceled.

In addition, more than 600 flights through New York’s three airports (LaGuardia, John F. Kennedy International and Newark Liberty International) have been canceled, 200 flights through Boston’s Logan International Airport have been halted, and 290 flights through Cleveland Hopkins International Airport have been nixed. The Washington area is not immune, with more than 300 flights through Reagan National, Dulles International and Baltimore-Washington International airports scrapped as well.

The pain is being felt across the country. Airports in Chicago and New York, among others, are key hubs in the nation’s aviation system. Cancellations are stopping flights to spots ranging from Indianapolis to Houston and from Denver to Orlando. The end result for many travelers is long lines at airport kiosks and compounding delays.

Monday’s travel pains follow similar issues last week. Scores of travelers, many returning home from holiday trips, were impacted on Thursday and Friday, with the midweek snow that had coated the Midwest moving to the Northeast by Thursday evening and into early Friday morning. The snowfall resulted in thousands of canceled and delayed flights across the Northeast and beyond, with those problems in turn reverberating out to other airports.

The difficulties continued into the weekend, with more than 1,700 flights canceled on Saturday and more than 3,800 flights halted on Sunday, FlightAware said. A plane skidded off the runway at John F. Kennedy International Airport on Sunday morning, closing that airport for a brief period.

As travelers cope with the mounting misery, airlines are relaxing restrictions on changing flights. United Airlines and JetBlue are waiving change fees and any fare differences for travel through multiple places (including Washington and Baltimore). US AirwaysDelta and Southwest are also not charging change fees for certain locations.

This post has been updated to include the latest number of flight delays. Last update: 4:30 p.m.