Frozen to a standstill Foot traffic only ... a couple cross New York's Brooklyn Bridge through the blizzard. A vast storm system descended on the densely populated US north-east, bringing high winds and snow drifts that forced the cancellation of 4700 flights, closed highways and threatened to leave hundreds of thousands without power. Five states - New York, Massachusetts, Connecticut, New Hampshire and Rhode Island - declared states of emergency, and Massachusetts banned vehicles from every road in the state. As dusk fell on Friday, conditions quickly deteriorated. Major highways were almost completely abandoned. The storm was forecast to bring the heaviest snow so far this winter along the New England coast, threatening power and transport links for tens of millions of people. By late on Friday, New York, one of the world's busiest air travel hubs, was cut off from the skies as snow and wind led airlines to suspend all operations at LaGuardia, Newark Liberty and John F. Kennedy International airports. "Conditions are not good for travel in any shape or form," said Kerry Schwindenhammer, a senior meteorologist at Accuweather in State College, Pennsylvania. We'd recommend people not even try. This is going to be a historic storm. There will be heavy snow, and there will be blizzard conditions, and that's going to cause some damage. In Massachusetts alone, more than 255,000 homes and businesses were without power by late evening and the number was expected to rise, the Boston Herald reported. The worst was still to come, at least in New England. Forecasters said the storm would continue through Saturday afternoon and winds could reach 120km/h, leaving behind a fresh white blanket perhaps a metre thick. A gust of 119km/h was already reported on Nantucket Island. The storm came a little over three months after hurricane Sandy devastated swathes of New York and New Jersey, killing 132 people and causing damage worth $US71.4 billion ($69.8 billion). In New York City, mayor Michael Bloomberg told people to stay home and warned them not to "panic buy" petrol because the supply was plentiful. But the memory of hurricane Sandy in October was still so raw that many across the region went on buying sprees anyway, emptying store shelves and filling extra containers in addition to their car tanks. In Massachusetts, Governor Deval Patrick took the unusual step of ordering all vehicles off all roads, not just state roads, by 4pm Friday, well before the brunt of the storm had hit. Violators could face up to a year in prison and a fine, though exceptions were made for emergency workers, the news media and anyone with a snowplough. "Two or three feet of snow is a profoundly different kind of storm than we have dealt with," the governor said from the state's emergency bunker in Framingham. Officials recalled only one previous such traffic ban, in the aftermath of the Blizzard of 1978, when more than 60 centimetres of snow paralysed the region, forcing people to abandon their cars in the middle of roadways. Maine declared a partial emergency, allowing it to suspend federal transportation rules, extend worker hours and bring in extra crews from Canada to assist with damage repair. Boston's transit system, including subway, buses and commuter rail lines, suspended service at 3.30pm, allowing first-shift workers to get home and second-shift workers to get to work. Schools throughout New Jersey, Connecticut, Massachusetts and Rhode Island were shut or sent students home early. Residents were comparing the storm to the ferocious blizzard of 1978, which killed 100 people and buried Boston in more than 69 centimetres of snow. The New York Times, Agence France-Presse, Bloomberg