Delta, United Cancel Hundreds of Flights Christmas Weekend Due to Omicron Variant

United and Delta have canceled hundreds of flights during the Christmas weekend due to the impacts of the rapidly spreading omicron variant.

According to flight-tracking site Flight Aware, both airlines have canceled nearly 300 flights each, between Dec. 23-25.

"The nationwide spike in omicron cases this week has had a direct impact on our flight crews and the people who run our operation," United told Travel + Leisure in a statement on Friday. "As a result, we've unfortunately had to cancel some flights and are notifying impacted customers in advance of them coming to the airport. We're sorry for the disruption and are working hard to rebook as many people as possible and get them on their way for the holidays."

The airline advises passengers to also monitor Flight Aware for the latest updates.

Similarly, Delta explained that they're working urgently to rectify the situation.

"Delta teams have exhausted all options and resources — including rerouting and substitutions of aircraft and crews to cover scheduled flying — before canceling around 135 flights for Friday," a Delta spokesperson told T+L. "Delta people are working hard to get them to where they need to be as quickly and as safely as possible on the next available flight. Customers are encouraged to check delta.com or the Fly Delta app for updates related to their specific flight."

Cancellations are also due to potential inclement weather.

Across the pond, German airline Lufthansa has also been dealing with flight cancellations due to pilot shortages, The Associated Press reported.

While this is not the first time staffing shortages due to COVID-19 have impacted flight schedules, the omicron variant has turned the busy holiday season into the most stressful time of the year as cases of COVID-19 have dramatically increased in the lead-up to Christmas.

In New York City, beloved holiday traditions like the "Christmas Spectacular" show at Radio City has canceled remaining performances while the typically massive New Year's Eve Celebration in Times Square has been scaled back, Mayor Bill de Blasio announced Thursday.

Recently, medical experts shared advice with T+L on how to proceed with caution while the omicron variant is still spreading.

"The low-risk people who are vaccinated and boosted, under 65, [and] don't have medical conditions are probably at relatively low risk for themselves. However, they could still be contributing to spread in the community," Dr. Keith Roach, associate attending physician at New York-Presbyterian and associate professor of clinical medicine at Weill Cornell Medicine, told T+L recently. "Things are completely different now from how they were three and four weeks ago. So we all have to be flexible about our travel plans."

The Centers for Disease Control and Prevention has maintained that getting vaccinated and boosted is the most effective way to mitigate the virus, while precautionary measures like mask-wearing and avoiding gatherings without social distancing are highly encouraged.

Christine Burroni is Travel + Leisure's Digital News Editor. Find her keeping up with just about everything on Twitter or see what she's up to in NYC or on her latest trip on Instagram.