The death toll from Superstorm Sandy has risen to at least 72 people, as populations along the East Coast of the United States prepare to take the first steps towards returning to their daily routines.
New York's three major airports are expected to be open later, offering stranded passengers a limited number of flights.
Some services on the city's subway system - which suffered the worst damage in its 108-year history - will also resume.
About six million homes and businesses remain without power, mostly in New York and New Jersey, and some 20,000 people are still trapped at home in a single New Jersey city.
National Guard troops have arrived in the heavily flooded city of Hoboken, just across the river from New York City, to help evacuate the 20,000 stranded residents.
Electricity outages continue as far west as Wisconsin in the Midwest and as far south as the Carolinas.
Restoring the usually vibrant New York City to its ordinarily frenetic pace could take days, while rebuilding the hardest-hit communities and the transportation networks could take considerably longer.
Power company Consolidated Edison says it could be the weekend before power is restored to Manhattan and Brooklyn, perhaps longer for other New York boroughs and the New York suburbs.
There are still only hints of the economic impact of the storm.
Forecasting firm IHS Global Insight predicted it would cause \$20bn in damage and \$10bn to \$30bn in lost business. Another firm, AIR Worldwide, estimated losses up to \$15bn.
Amtrak said the amount of water in train tunnels under the Hudson and East rivers was unprecedented, but it said it planned to restore some service on Friday to and from New York City.
Speaking on Wednesday, US President Barack Obama told New Jersey residents that the government will support them "for the long haul".
The region took the brunt of its impact and is among the worst affected areas on the East Coast.
Joined by New Jersey Governor Chris Christie, Mr Obama - who described the disaster as "heartbreaking for the nation" - inspected the impact from Sandy, flying high over flooded neighbourhoods and sand-strewn streets.
He told those affected by the storm: "Our hearts go out to the families who have lost loved ones. Their world has been torn apart ... they are in our thoughts and prayers.
"For those like the people I have had a chance to meet on this block, throughout New Jersey and throughout the region whose lives have been upended, my second message is: We are here for you, and we will not forget, we will follow up to make sure that you get all the help that you need until you've rebuilt."
