New York, New York - Forecasters warned on Friday that a deluge of snow and wintery conditions could bring travel chaos to the northeast this weekend, with some 25 million people subject to a storm warning.

Several cities in the eastern United States, including New York, the most populous city in the country, have gone record periods without winter snowfall.

But the National Weather Service (NWS) said in a winter storm warning that "travel could be nearly impossible" in places over the weekend, threatening chaos for travelers returning from winter breaks.

The affected area stretches from just outside Boston, inland across the northeast through parts of New England, and down towards Baltimore and Washington, DC.

Environment and Climate Al Gore says climate progress "won't slow much" because of Trump – here's why

Ice was likely to cause power outages and fell trees, forecasters warned.

"[A] winter storm watch has been issued for Saturday morning through Saturday evening," the NWS said in a forecast that warned up to three inches of snow and sleet could accumulate in the most highly-populated areas.

"Low pressure will bring wintry precipitation to portions of the region Saturday into Saturday evening."

Portions of northern Connecticut and swathes of Massachusetts could face snow accumulations of between six and 12 inches as well as wind gusts of up to 40 miles per hour, the NWS warned, adding that forecasts could still change.

The governor of New York state, which includes the eponymous megacity, ordered an emergency response in anticipation of the large coastal weather system bearing down on the region.

"We anticipate heavy, wet snowfall across various regions, potentially causing power outages and hazardous travel. I urge New Yorkers to be vigilant," said Governor Kathy Hochul in a statement.

In 2022, the northeast was battered by what authorities called the "blizzard of the century" that left dozens dead.

A perfect storm of fierce snow squalls, howling wind, and sub-zero temperatures hobbled transportation and caused widespread power outages.

Scientists say human-caused climate change, brought about by the unchecked burning of fossil fuels, is making winter storms wetter and wilder.