At the stock exchange, running on generator power, Mayor Michael Bloomberg gave a thumbs-up and rang the opening bell to whoops from traders on the floor. Trading resumed after the first two-day weather shutdown since the Blizzard of 1888.
New York's subway system was still down, but Kennedy and Newark Liberty airports reopened with limited service just after 7 a.m. New York's LaGuardia Airport, which suffered far worse damage and where water covered parts of runways, remained closed.
It was clear that restoring the region to its ordinarily frenetic pace could take days — and that rebuilding the hardest-hit communities and the transportation networks that link them could take considerably longer.
About 6.5 million homes and businesses were still without power, including 4 million in New York and New Jersey. Electricity was out as far west as Wisconsin and as far south as the Carolinas.
The scale of the challenge could be seen across the Hudson River in New Jersey, where National Guard trucks rolled into heavily flooded Hoboken to deliver ready-to-eat meals and other supplies and to evacuate people from their condo high-rises, brownstones and other homes.
The mayor of the city of 50,000 issued an appeal for people to bring boats to City Hall to help with the evacuation.
And new problems arose when firefighters were unable to reach blazes rekindled by natural gas leaks in the heavily hit shore town of Mantoloking. More than a dozen homes were destroyed.
As the extent of the devastation became clear, New Jersey Gov. Chris Christie issued an order postponing Halloween trick-or-treating until Monday, saying floodwaters, downed power lines, outages and fallen trees make it too dangerous for children to go out.
President Barack Obama planned to visit Atlantic City, N.J., which was directly in the storm's path Monday night and where part of the historic boardwalk washed away.
Outages in the state's two largest cities, Newark and Jersey City, left traffic signals dark, resulting in fender-benders at intersections where police were not directing traffic. At one Jersey City supermarket, there were long lines to get bread and use an electrical outlet to charge cellphones.
Amid the despair, talk of recovery was already beginning.
"It's heartbreaking after being here 37 years," Barry Prezioso of Point Pleasant, N.J., said as he returned to his house in the beachfront community. "You see your home demolished like this, it's tough. But nobody got hurt and the upstairs is still livable, so we can still live upstairs and clean this out. I'm sure there's people that had worse. I feel kind of lucky."
As New York began its second day after the megastorm, morning rush-hour traffic was heavy as people started returning to work. There was even a sign of normalcy: commuters waiting at bus stops. School was out for a third day.
The Brooklyn-Battery Tunnel, connecting Brooklyn to Manhattan, and the Holland Tunnel, between New York and New Jersey, remained closed. But bridges into the city were open, and city buses were running, free of charge.
On the Brooklyn Bridge, closed earlier because of high winds, joggers and bikers made their way across before sunrise. One cyclist carried a flashlight. Car traffic on the bridge was busy.
Bloomberg said it could be the weekend before the subway, which suffered the worst damage in its 108-year history, is running again. High water prevented inspectors from immediately assessing damage to key equipment.
The chairman of the state agency that runs the subway, Joseph Lhota, said service might have to resume piecemeal, and experts said the cost of the repairs could be staggering.
Power company Consolidated Edison said it could also be the weekend before power is restored to Manhattan and Brooklyn, perhaps longer for other New York boroughs and the New York suburbs.
The recovery and rebuilding will take far longer.
When Christie stopped in Belmar, N.J., during a tour of the devastation, one woman wept, and 42-year-old Walter Patrickis told him, "Governor, I lost everything."
Christie, who called the shore damage "unthinkable," said a full recovery would take months, at least, and it would probably be a week or more before power is restored to everyone who lost it.
"Now we've got a big task ahead of us that we have to do together. This is the kind of thing New Jerseyans are built for," he said.
Amtrak trains were still not running in or out of New York's Penn Station because of flooding in the tunnels.
In Connecticut, some residents of Fairfield returned home in kayaks and canoes to inspect the flood damage.
"The uncertainty is the worst," said Jessica Levitt, who was told it could be a week before she can enter her house. "Even if we had damage, you just want to be able to do something. We can't even get started."
In New York, residents of the flooded beachfront neighborhood of Breezy Point in returned home to find fire had taken everything the water had not. A huge blaze destroyed perhaps 100 homes in the close-knit community where many had stayed behind despite being told to evacuate.
John Frawley acknowledged the mistake. Frawley, who lived about five houses from the fire's edge, said he spent the night terrified "not knowing if the fire was going to jump the boulevard and come up to my house."
"I stayed up all night," he said. "The screams. The fire. It was horrifying."
Forecasting firm IHS Global Insight predicted it would cause $20 billion in damage and $10 billion to $30 billion in lost business. Another firm, AIR Worldwide, estimated losses up to $15 billion.