On New Year's Day, Thousands Of Flights Were Canceled Due To Omicron And Bad Weather.

 The new year picked up where the previous one left off for air travelers — with a lot of frustration.

According to flight tracking service FlightAware, more than 2,400 flights in the United States and almost 4,200 globally had been canceled by late Saturday morning on the East Coast.

This is the highest single-day toll since just before Christmas, when airlines began blaming rising COVID-19 infections among crews on staffing shortages. Since December 24, almost 12,000 flights in the United States have been canceled.

The virus wasn't the only cause of Saturday's problems. Chicago was the worst spot in the country for travelers due to the winter weather, with 800 flights canceled at O'Hare Airport and more than 250 at Midway Airport.

Nine inches of snow was expected, according to forecasts. At least 100 flights were canceled in Denver, Detroit, and Newark, New Jersey.

Southwest Airlines, which has significant hubs in Chicago Midway and Denver, had canceled more than 450 flights nationally by midday, accounting for 13% of its schedule. American, Delta, United, and JetBlue each canceled over 100 flights.

SkyWest, a regional carrier that flies under the brands American Eagle, Delta Connection, and United Express, has canceled over 400 flights, or 21% of its scheduled flights.