The harsh winter weather that has disrupted air travel in recent times continues to pose a problem for vacation travelers.
As of Monday afternoon, more than 3,600 flights to and from the United States have been canceled, according to FlightAware, which tracks global flight data.
Meanwhile, trackers showed that about 6,000 flights to or from U.S. airports experienced delays.
The number of US-based cancellations on Monday is higher than the aggregated Christmas Day total of 3,184.
Southwest Airlines canceled two-thirds of all flights on Monday, but that total could increase as current delays turn into eventual cancellations. Other major airlines, including Delta, United and JetBlue, have canceled less than 10% of all flights, according to FlightAware.
“The volume of calls and social inquiries continues to be high,” Southwest wrote on Twitter before introducing passengers to the self-service link. According to airlines, the average talk time over Christmas has averaged over two hours, and has gone up to four hours.
Passengers are stranded at airports due to high winds, snow and ice conditions from the critical winter system that hit across the country last week and over the weekend.
Temperatures are expected to warm up by the end of the week, which should ease some of the strain on airlines over canceled flights.