MIAMI (NewsNation Now) — Flight cancellations and delays are continuing into the New Year after a holiday season riddled with travel disruptions amid the spread of the omicron variant and severe weather.

As of 8 a.m. ET Friday, at least 2,200 U.S. flights were canceled and more than 4,000 flights were delayed, according to tracking service FlightAware.

The Christmas and New Year holidays are typically a peak time for air travel, but the rapid spread of the highly transmissible omicron variant has led to a sharp increase in COVID-19 infections, forcing airlines to cancel flights as pilots and cabin crew quarantine.

U.S. health officials halved guidance to five days of quarantine for asymptomatic Americans who catch the coronavirus. Airline industry experts say that will alleviate the staffing issues that have forced airlines to scratch flights — but the flight attendant unions say they’re wary of the change and its effect on worker health.

Travel experts say passengers should expect to see delays and cancelations for at least another couple of weeks.

“I don’t think you’re gonna see a big drop in cancellation unfortunately for the next month as the sort of Omicron variant wave peaks and then hopefully recedes quickly,” said travel expert, Clint Henderson. “I’m not sure I would tell consumers or leisure travelers to cancel their trip. I would tell folks who have trips planned to have a backup plan.”

As of Friday morning, Southwest continued to be the hardest hit among U.S. airlines, canceling about 520 flights, or 17% of its schedule for Friday by early morning.

Alaska Airlines said Thursday it will trim its schedule by about 10% for the rest of January as it deals with “unprecedented” numbers of employees calling in sick during the COVID-19 surge.

The move by Alaska is similar to a decision last week by JetBlue Airways to cut about 1,300 flights through mid-January.