Another 3,700 flights cancelled Sunday; almost all at Newark nixed

As of Sunday morning, nearly 3,700 flights had been cancelled for the day across the country, most of them in the northeast.

Nearly another 2,000 were delayed, according to FlightAware.com. Those service disruptions followed more than 5,200 cancellations and 5,000 delays on Saturday, when a massive snowstorm pummeled the northeast.

United Airlines expected to restart "limited service" from Newark Liberty Airport on Sunday, but as of Sunday morning, the vast majority of flights into or out of Newark were cancelled.

LaGuardia airport in Queens had 669 cancellations as of Sunday morning, more than 70 percent of the day's schedule.

"From a percentage basis, Baltimore-BWI is most impacted with 79 percent of flights cancelled," FlightAware wrote in a news release Sunday morning. "JFK, Newark-EWR, Dulles-IAD, and Reagan National-DCA are all seeing 50 to 60% of flights cancelled today."

All major airlines issued waivers for travel over the weekend, allowing passengers to rebook onto earlier or later flights to avoid the storms.

The airports included vary by airline, but they include departures and destinations in Kentucky, Tennessee and West Virginia all the way up the coast to New Hampshire and Massachusetts.

Flightaware said that by Sunday morning, it was seeing more than 600 cancellations on Monday as well — though none yet on Tuesday.

— With reporting by Dan Alexander and the Associated Press