DALLAS (CBSDFW.COM/AP) — Wintry weather combined with the pandemic to frustrate air travelers whose return flights home from the holidays were canceled or delayed in the first days of the new year.

More than 2,500 U.S. flights and more than 4,100 worldwide were grounded Sunday, according to tracking service FlightAware.

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Air travelers wear masks and are separated by plexiglass as they make their way through security at Love Field in Dallas. (Credit: AP Photo/LM Otero)

That followed Saturday’s mass cancelations of more than 2,700 U.S. flights, and more than 4,700 worldwide. Saturday’s single-day U.S. toll was the highest since just before Christmas, when airlines began blaming staffing shortages on increasing COVID-19 infections among crews.

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The FAA has also been plagued by staffing shortages. Last week, a staffing shortage related to multiple health and safety factors, including COVID-19, resulted in the temporary closure of the air traffic control tower on the west side of DFW Airport.

A winter storm that hit the Midwest on Saturday made Chicago the worst place in the country for travelers throughout the weekend as the region’s airports continued to recover Sunday morning. About a quarter of all flights at O’Hare Airport were canceled Sunday.

American Airlines said most of Sunday’s canceled flights had been canceled ahead of time to avoid last-minute disruptions at the airport.

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(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)

CBSDFW.com Staff