Americans love to travel in droves over the Christmas holiday season, but many of those choosing to fly had a rough go of it this weekend.

US airlines called off more than 1,100 flights on Sunday, the day after Christmas, as crews were grounded amid rising coronavirus infections driven by the Omicron variant.

FlightAware.com reported that as of 6 pm EST Sunday, there were 1,183 flight cancellations in the US. Total delays within, into or out of the United States were reported at 4,892.

Globally, there were 12,693 delays and 2,838 cancellations.

It was the third straight day of airline disruptions. There were 997 flights shelved on Christmas Day and nearly 700 on Christmas Eve.

The American Automobile Association estimated on Dec 14 that more than 109 million Americans would travel 50 miles or more by plane, train or automobile between Dec 23 and Jan 2, a 34 percent increase over last year.

With the specter of Omicron, the normally joyous, exciting time of year turned to exasperation for many, particularly flyers.

Staffing shortages blamed on Omicron and in some instances the weather were reasons being given for the widespread flight cancellations.

"Like many businesses and organizations, we have seen an increasing number of sick calls from Omicron," a spokesperson for New York-based Jet Blue said in a statement, CNBC reported. "Despite our best efforts, we've had to cancel a number of flights, and additional flight cancellations and other delays remain a possibility as we see more Omicron community spread."

Others online blamed the chaos on airlines that furloughed or fired employees who declined COVID-19 vaccines. United, one of the airlines reporting the most delays over the holiday weekend, let go 200 such workers in October.

United Airlines had to cancel around 100 flights on Sunday, a spokesperson said.

One Twitter user wrote on Saturday: "you guys already cancelled my flight just 2 hours before the flight. Do u think ppl have time for that s---?. NO!! I'm already in NYC. And I'll be sure to NOT buy another flight with United. Thanks for ur prompt response, too bad ur service dont live up to the expectation."

Enjoli Rodriguez, 25, whose Delta Air Lines flight from Los Angeles to Lexington, Kentucky, was canceled on Christmas Eve due to COVID-related staffing shortages, was one of the thousands still stranded on Sunday.

Speaking from the Detroit airport on Sunday, Rodriguez said she was surrounded by angry passengers, flustered airline representatives and families with young children in limbo.

"I've run into a lot of people sharing their horror stories here. We're all just stuck in Michigan, Detroit, heading different places," Rodriguez told Reuters. She was rebooked on a later flight to Kentucky.

With the surge in infections, airlines have been forced to cancel flights with pilots and cabin crew needing to quarantine. Poor weather in some areas also contributed to the problems.

"Winter weather in portions of the US and the Omicron variant continued to impact Delta's holiday weekend flight schedule," a spokesperson for the airline said in an emailed statement, adding that it was working to "reroute and substitute aircraft and crews to get customers where they need to be as quickly and safely as possible".

A spokesperson for Southwest Airlines said all of their cancellations were weather related.

The US airports most affected by the cancellations, in order, were Denver, Seattle, Salt Lake City, Chicago and Los Angeles, according to FlightAware's "Misery Map".

"Anti-icing and snow removal is ongoing on runways, taxiways and the ramp areas. Each airline is responsible for de-icing its aircraft," said a tweet Sunday by the Seattle-Tacoma International Airport.

Omicron was first detected in November and now accounts for nearly three-quarters of US cases and as many as 90 percent in some areas, such as on the Eastern Seaboard.

The average number of new US coronavirus cases has risen 45 percent to 179,000 per day over the past week, according to Reuters.

The New York state health department said the virus numbers were concentrated in New York City and surrounding areas where Omicron is spreading rapidly. According to the city website, 82.6 percent of New York City adults are fully vaccinated.

The city's emergency medical services crews were short staffed on Christmas Day, as hundreds called out sick — while those on the job had to respond to more than 4,000 calls, the New York Daily News reported, saying nearly 19 percent of the city's 4,000-plus EMS workers called out sick Saturday. The average sick-day rate is about 5 percent.

Reuters contributed to this story.