Thousands of flights canceled, delayed as COVID-19 hits record levels

Dec. 29 (UPI) -- Air travel faced another day of delays and cancellations Wednesday as inclement weather and the spread of the Omicron variant of COVID-19 put strains on airline schedules and staffing.

Flight tracking website FlightAware reported 2,556 cancellations worldwide as of midday, with 867 into or out of the United States. Total delays Wednesday towered to more than 7,700, one-third of which were for flights into or out of the United States.

Seattle-Tacoma International Airport reported the highest number of cancellations into and out of the site, followed by several Chinese airports in the Top 10. Delays were highest out of Hartsfield-Jackson Atlanta International Airport and into Dallas-Fort Worth International Airport.

Wednesday continued several days of air travel disruptions, with more than 3,000 flights canceled Christmas Eve and Christmas Day as flight crews, attendants and other airline employees called in sick due to COVID-19.

COVID-19 cases have ballooned globally in recent weeks, reaching a new record for confirmed daily cases Wednesday of at least 1.35 million, according to the World Health organization. In the United States, which hasn't reported its Wednesday totals yet, there were 441,278 new cases reported Tuesday, the highest single-day total since the start of the pandemic, according to the U.S. Centers for Disease Control and Prevention.

Winter weather systems have also played a role in air travel disruptions, with storms predicted to spread winter weather across much of the Midwest and Northwest.

Alaska Airlines blamed the adverse winter weather expected to last through Thursday for canceling some 170 flights Wednesday. A news release from the airline said the cancellations will allow the additional time needed to deice aircraft.

"We deeply apologize for the inconvenience this winter storm has on our guests and employees and are working hard to return to the level of service you know and expect from us, while operating safely," said Constance von Muehlen, chief operating officer and executive vice president of Alaska Airlines.