Emergency crews in New York were scrambling Monday to rescue marooned residents from what authorities called the "blizzard of the century," a relentless storm that has left at least 25 dead in the state and is causing US Christmas travel chaos.

Blizzard conditions continue to prevail in parts of the US Northeast, the stubborn remnants of a massive sprawl of extreme weather that gripped the country over several days, causing widespread power outages, travel delays and at least 47 deaths across nine states.