"This could be a storm the likes of which we have never seen before," New York City Mayor Bill de Blasio said during a news conference in Manhattan Sunday afternoon.
Flights are being cancelled from Montreal to New York’s LaGuardia Airport as of 10:50 a.m. ET and to New Jersey’s Newark Liberty International Airport as of 1:40 p.m. ET.
Earlier flights are still scheduled to leave as planned, though departures could still be changed.
Between 60 and 90 cm of snow is predicted to fall in an area stretching from Philadelphia to Maine.
Hundreds of flights in the northeast U.S. have been cancelled already and about 1,700 scheduled for Monday are expected to be grounded.
Delta Airlines has already cancelled 600 flights.
United is in the process of cancelling flights in Boston, New York and Philadelphia.
Amtrak says it is planning to operate trains on a normal Monday schedule, but may re-evaluate.
Train crews are monitoring the latest forecasts and planning for the possibility that service adjustments may be necessary.
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