NEWARK, N.J. — The winter storm blasting through the northeastern U.S. has caused massive cancellations and delays at the New York area’s major airports.

The Port Authority of New York and New Jersey says all flight activity at JFK Airport has been suspended Thursday. Flights are to resume at 7 a.m. Friday.

Air traffic at LaGuardia was also suspended Thursday but that suspension has since been lifted.

AirTrain service to JFK has been suspended and replaced by bus service.

At Newark Liberty International Airport, more than 850 flights have been cancelled, about 73 percent of normal flight activity. Newark’s AirTrain is out of service from the rail station to the P4 parking lot, replaced by bus service.

Stewart International Airport in New Windsor, New York, is open and four flights have been cancelled.