Residents and businesses began a massive clean-up effort Tuesday, even as large parts of the region remained without power, and transportation in the New York metropolitan area was at a standstill.
The most devastating storm in decades to hit the country's most densely populated region upended man and nature as it rolled back the clock on 21st-century lives, cutting off modern communication and leaving millions without power Tuesday as thousands who fled their water-menaced homes wondered when — if — life would return to normal.
A weakening Sandy, the hurricane turned fearsome superstorm, killed at least 50 people, many hit by falling trees, and still wasn't finished. It inched inland across Pennsylvania, ready to bank toward western New York to dump more of its water and likely cause more havoc Tuesday night. Behind it: a dazed, inundated New York City, a waterlogged Atlantic Coast and a moonscape of disarray and debris — from unmoored shore-town boardwalks to submerged mass-transit systems to delicate presidential politics.
"Nature," said New York City Mayor Michael Bloomberg, assessing the damage to his city, "is an awful lot more powerful than we are."
More than 8.2 million households were without power in 17 states as far west as Michigan. Nearly 2 million of those were in New York, where large swaths of lower Manhattan lost electricity and entire streets ended up underwater — as did seven subway tunnels between Manhattan and Brooklyn at one point, the Metropolitan Transportation Authority said.
The New York Stock Exchange was closed for a second day from weather, the first time that has happened since a blizzard in 1888. The shutdown of mass transit crippled a city where more than 8.3 million bus, subway and local rail trips are taken each day, and 800,000 vehicles cross bridges run by the transit agency.
Consolidated Edison, the power company, said it would be four days before the last of the 337,000 customers in Manhattan and Brooklyn who lost power have electricity again. Problems to its high-voltage systems caused by the hurricane forced the utility to cut power Tuesday night to an additional 160,000 customers in Brooklyn and Staten Island.
For the Bronx, Queens, Staten Island and Westchester County, with 442,000 outages, it could take a week, Con Ed said. Floodwater led to explosions that disabled a power substation on Monday night, contributing to the outages.
By Tuesday evening, the remnants of Sandy were about 50 northeast of Pittsburgh, pushing westward with winds of 45 mph. It was expected to turn toward New York State and Canada during the night.
Although weakening as it goes, the storm will continue to bring heavy rain and flooding, said Daniel Brown of the National Hurricane Center in Miami.
The storm hit with just a week to go to the Nov. 6 presidential election, disrupting campaigning and early voting and raising questions about whether polling stations in some hard-hit communities would be ready to open by Tuesday.
Across the region, crews began the monumental task of restoring power for anxious customers and getting transportation up and running could take time after the storm caused more than 18,000 flight cancellations worldwide.
The Port Authority of New York and New Jersey says John F. Kennedy International Airport in New York and Newark International Airport in New Jersey will open at 7 a.m. Wednesday with limited service. They were closed in the storm. LaGuardia Airport remains closed. It's unclear what carriers will have flights operating.
The Port Authority says some carriers will be landing planes with no passengers at JFK starting Tuesday night to be prepared for flights the next day.
Cellphone service outages were widespread in many states and even some emergency call centers were affected.
Parts of West Virginia were buried under 3 feet of snow, a boon for ski resorts that was one of the storm's few bright spots. Some cities like Washington, Philadelphia and Boston were spared the worst effects of the storm and were ready to return to normal by Wednesday. But New York City, large parts of New Jersey and some other areas will need at least several days to get back on their feet.
"The devastation is unthinkable," New Jersey Governor Chris Christie said after seeing pictures of his state's shore.
Seeking to show he was on top of the aftermath of the storm in the nation's most densely populated region, the White House said President Obama planned to tour damaged areas of New Jersey on Wednesday accompanied by Christie.
The New Jersey governor, who has been a strong supporter of Republican presidential challenger Gov. Mitt Romney, praised Obama and the federal response to the storm.
"New Jersey, New York in particular have been pounded by this storm. Connecticut has taken a big hit," Obama said during a visit to Red Cross headquarters in Washington.
Obama issued federal emergency decrees for New York and New Jersey, declaring that "major disasters" existed in both states.
Power outages darkened large parts of Manhattan and a fire destroyed more than 80 homes in New York City's borough of Queens, where flooding hampered firefighting efforts.
"To describe it as looking like pictures we've seen of the end of World War II is not overstating it. The area was completely leveled. Chimneys and foundations were all that was left of many of these homes," said Bloomberg after touring the area.
Neighborhoods along the East and Hudson rivers bordering Manhattan were underwater and expected to be without power for days, as were low-lying streets in Battery Park near Ground Zero, where the World Trade Center once stood.
"I'm lucky to have gas; I can make hot water. But there is no heating and I'm all cold inside," said Thea Lucas, 87, who lives alone in Manhattan's Lower East Side.
Further north, though, many retail stores, restaurants and bars reopened in neighborhoods that did not lose power.
By Tuesday afternoon, there were still only hints of the economic impact of the storm. Airports remained closed across the East Coast and far beyond as tens of thousands of travelers found they couldn't get where they were going.
Forecasting firm IHS Global Insight predicted the storm will end up causing about $20 billion in damages and $10 billion to $30 billion in lost business. Another firm, AIR Worldwide, estimated losses up to $15 billion — big numbers probably offset by reconstruction and repairs that will contribute to longer-term growth.
"The biggest problem is not the first few days but the coming months," said Alan Rubin, an expert in nature disaster recovery.
Sandy began in the Atlantic and knocked around the Caribbean — killing nearly 70 people — and strengthened into a hurricane as it chugged across the southeastern coast of the United States. By Tuesday night it had ebbed in strength but was joining up with another, more wintry storm — an expected confluence of weather systems that earned it nicknames like "superstorm" and, on Halloween eve, "Frankenstorm."
It became, pretty much everyone agreed Tuesday, the weather event of a lifetime — and one shared vigorously on social media by people in Sandy's path who took eye-popping photographs as the storm blew through, then shared them with the world by the blue light of their smartphones.