THE northeast US, including New York City, prepared for heavy snow, strong winds and frigid temperatures as Canada recorded temperatures colder than Mars.

Snow began falling overnight in parts of New England and New York, but the real force of the storm was expected later Thursday and into Friday. Temperatures were expected to drop well below freezing, according to the National Weather Service.

"There will be travel problems,'' said Hugh Johnson, a weather service meteorologist.

About 1000 US flights were cancelled for Thursday, with Chicago's O'Hare and New Jersey's Newark Liberty International airports the most affected.

Up to 14 inches (355 millimetres) of snow is forecast for the Boston area, and the National Weather Service issued a blizzard warning for Long Island outside New York City, where up to 10 inches (254 millimetres) of snow was expected.

The storm may be the first test of New York City's new mayor, Bill de Blasio, who was sworn in on Wednesday. The city, expected to get up to 7 inches (177 millimeters), issued a snow alert.

Meanwhile in Canada Winnipeg had its coldest day in 80 years, temperatures plunged to -37.9 C With the windchill factor it felt like -48 C.

"According to the Curiosity Rover, Mars reached a maximum air temperature of -29°C today. Winnipeg's high was -31°C," the Manitoba Museum posted on Twitter.

The North Pole was also 10 degrees warmer than Winnipeg.

The storm dropped a half-foot or more of snow in Illinois on Wednesday, prompting hundreds of flight cancellations into and out of Chicago's O'Hare International Airport, according to the aviation tracking website FlightAware.com.

Authorities said the weather may have been a factor in a fatal crash involving a pickup and a bus carrying casino patrons in Indiana. Police said the truck's driver was killed and 15 bus passengers were hurt in the collision on a snow-covered and slushy highway in Rolling Prairie.

Sections of interior southern New England and New York could get up to a foot of snow, with forecasts generally calling for up to a foot.

While the bulk of the snow was expected to hit southern New England and southern sections of Maine, New Hampshire and Vermont, the prospect of additional snow was welcome news for many areas farther north.

In Maine, where some communities are still recovering from a recent ice storm that cut power to more than 100,000 customers, people seemed prepared for more winter weather.

Kelly St. Denis, of Auburn, went skiing on Wednesday at the Sunday River ski area with family and friends. She said it's been cold but the skiing has been good.

"Hey, it's winter in Maine,'' she said. "We go with it.''