Last update: 6:30 p.m. ET. Next update: By 9 p.m. ET

Holiday travelers faced more flight delays in the Northeast and mid-Atlantic on Friday, the busiest air-travel day of the Christmas period.

The disruption comes as a sprawling storm moved north along the East Coast. The system brought a mix of heavy rain, strong winds and poor visibility to airports from Florida to New England from Thursday into Friday.

The weather hasn’t been severe enough for force widespread cancellations like a snowstorm might, but it has resulted in thousands of delays at dozens of major airports.

Nationwide, about 330 flights had been canceled Friday and another 6,245 delayed as of 4:25 p.m. ET, according to flight-tracking service FlightAware. The delay count rose throughout the day as poor weather affected airports near New York City, Philadelphia, Washington and Boston.



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Two big airlines – United and JetBlue – were waiving rebooking fees for some customers flying through New York City-area airports.

United, which operates one of its busiest hubs at New Jersey’s Newark Liberty airport, is waiving rebooking fees for Friday flyers scheduled to fly through four airports in the region (Newark, New York JFK, New York LaGuardia, and White Plains/Westchester, New York).

JetBlue’s waiver was similar, including those four airports plus Newburgh, New York – an alternate New York City airport about 60 miles north of Manhattan.

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No other big carriers were waiving change fees as of 1 p.m. ET on Friday.

The culprit for the disruptions in the region where winds, heavy rain and reduced visibility associated with the northward-moving storm. Problems could linger into Saturday for airports near New York City and Boston as strong winds were forecast to follow in the wake of the storm.

Friday's issues follow similar problems Thursday, when more than 8,080 flights were delayed nationwide. While the storm in the East caused many of those, foggy weather in San Francisco and windy weather in Seattle also created significant flight back-ups. Only about 260 flights were canceled in the U.S. on Thursday..

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