Abby Stanglin enjoyed her holiday trip to London, but her flight back to New York offered an unscheduled detour to Washington after a massive snowstorm closed John K. Kennedy International Airport on Thursday.

Airlines canceled nearly 4,400 cancellations Thursday, with another 1,263 by noon Friday, after a massive snowstorm disrupted travel plans up and down the East Coast a day earlier, according to FlightAware.com, an online tracking service. Dozens of flights from New York airports were diverted as airports in white-out conditions of blowing snow and high winds.

Stanglin’s Norwegian Airlines flight from Gatwick airport was diverted to Dulles International Airport, where the carrier doesn’t usually fly. The plane sat on the tarmac for two hours before passengers got off — and her luggage still hadn’t been unloaded by Friday morning — but travelers were able to clear customs and sleep in the airport.

Airport staffers helped at least three planeloads of passengers sleep in the part of the airport where she stayed, Stanglin said. The helpers included Margaret McKeough, chief operating officer for the airport, who spent the night as part of the working at the emergency operations center.

In the morning, the selection of muffins and croissants was good enough that Stanglin wants to track down the pastry chef.

“The really nice people gave us pillows and blankets and pastries,” said Stanglin, 34, of Brooklyn. “Tons of people on cardboard boxes on the ground.”

Blowing snow and high winds Thursday closed New York’s John F. Kennedy and LaGuardia airports, and greatly curtailed flights at Newark Liberty International Airport.

JFK remained closed until 7 a.m. Friday. LaGuardia and Boston Logan International Airport each began the day with one runway open, and each planned to open a second by mid-morning, according to FlightAware.com, which tracks flights online.

“Cancellations will continue at most Northeast airports through the morning as…