A major winter storm has battered northeastern US, causing widespread power outages, flight cancellations and school and business closures.

Thursday's severe weather came just a day after many of the northeastern cities basked in above average temperatures, with New York reaching 17C, Philadelphia hitting 19C and Boston 11C.

Yet that warm air was just the precursor to the winter storm that was moving rapidly out of the Midwest.

At one point on Thursday, more than 40 million people were under some sort of winter weather watch or warning.

Long Island New York, as well as parts of Rhode Island and eastern Massachusetts, were all under blizzard warnings for much of the day.

The warning also affected most of the major northeastern airports, forcing airlines to begin cancelling flights well in advance of the storm.

By the end of Thursday, more than 3,700 flights had been cancelled and hundreds more delayed owing to the storm, the strongest of the season so far.

From Pennsylvania to Maine, thousands of schools and government offices on Thursday also closed their doors, with only a small percentage of businesses staying open.

Some in New York City walked through unploughed streets and over snowbanks just to find delayed subways, while others worked from home.

Tens of thousands were also without power across many of the states as high winds brought down power lines and tree branches.

Hyannis, Massachusetts, recorded a wind gust of 113 kilometres per hour, while Worcester, Massachusetts hit a max wind of 97km/h.

Due to the much warmer weather in the days before, many areas across southern New England and the mid-Atlantic states were without any snow. Once the storm began, some areas saw snowfall rates as high as 5cm per hour.

The highest snowfall total was in East Hartford, Connecticut, with more than 48cm of snow; New York's Central Park saw almost 24cm; while at LaGuardia Airport ploughs were clearing the runways of the 25cm they received.

Much of the eastern seaboard began to clear by late on Thursday, as the storm moved out into the Canadian Maritimes.

But over the next seven days, three more winter storms are expected to move through the region, bringing even more snow to the already hard-hit cities.