NEW YORK (AFP) - The northeastern United States prepared Thursday for snow, high winds and frigid temperatures, as a gust of wintry weather bore down on New England and surrounding states, cancelling flights.

Temperatures in New York were expected to drop to -12 degrees Celsius with a windchill factor of -22 degrees Celsius, according to national weather forecasts.

Tracking system FlightAware said that 1,560 flights entering, leaving or inside the United States had been cancelled as of midday, as the National Weather Service issued a storm warning for parts of New England and New York, New Jersey and Pennsylvania.

Heavy winter weather was simultaneously hitting the country's midwest, dropping a blanket of snow and cancelling flights at Chicago's O'Hare International Airport.

The northeastern winter warning was in effect in New York from Thursday evening through midday Friday, with forecasters predicting six to 10 inches of snow and winds that could reach up to 72 kilometers per hour on Friday.

The National Weather Service issued a blizzard warning for New York's Long Island.

The storm in the Big Apple, where forecasters expect 3 to 7 inches of snow, will pose a first test for the city's new Mayor Bill de Blasio, who assumed his post Wednesday.

New York Governor Andrew Cuomo activated the State Emergency Operations Center and urged people to use public transportation, warning of possible highway closures due to inclement weather.

In Boston, temperatures had already dropped to -31 degrees Celsius Thursday morning. The state was under a winter storm warning, with strong snowfall expected until Friday.