Arriving and departing flights at New York City area airports gained steam early on Sunday evening after the worst US East Coast snowstorm in decades resulted in a deluge of cancellations and delays.

Arrivals and departures at LaGuardia, John F. Kennedy International, and Newark Liberty were observed on Sunday, although Washington airports were idle except for a dozen flights that were en route, the chief executive of FlightAware.com said in an email.

"There is light at the end of the tunnel - we are now seeing both arrivals and departures at the New York City area airports," said Daniel Baker, chief executive of the aviation website.

Airlines had canceled over 3,500 flights within, into, or out of the United States on Sunday as of 8:40 p.m. (0140 GMT). New York's LaGuardia topped the list of total cancellations with 348 scrubbed flights that were set to depart from the airport, or 76 percent of its planned total, according to FlightAware.com.

Other New York City area airports John F. Kennedy International and Newark Liberty followed with the second- and third-most canceled flights, respectively, at 326 and 309. Over 1,100 flights for Monday were canceled, with Newark Liberty most impacted at over 220 canceled flights, or over 40 percent of its planned total.

Overall, airlines have canceled over 12,000 flights across the five-day period of Friday-Tuesday, FlightAware.com's Baker said.

The blizzard was the second-biggest snowstorm in New York City history, with 26.8 inches (68 cm) of snow in Central Park by midnight on Saturday, just shy of the record 26.9 inches (68.3 cm) set in 2006, the National Weather Service said. – Reuters