Sandy battered the U.S. East Coast on Monday with fierce winds and driving rain, as the monster storm shut down transportation, shuttered businesses and sent thousands scrambling for higher ground.
Forecasters say Sandy is "moving quickly" and should make landfall by around 8pm ET Monday in southern New Jersey or Delaware.
In its 7pm ET update, the National Hurricane Center downgraded the storm to a post-tropical cyclone and said it's losing strength but the storm still has sustained winds of 85 mph.
The eye has almost made landfall and is headed for New Jersey and Delaware.
Sandy was set to collide with a wintry storm from the west and cold air streaming down from the Arctic. The combination superstorm could menace some 50 million people in the most heavily populated corridor in the nation, from the East Coast to the Great Lakes.
New York City Mayor Michael Bloomberg told residents Monday evening to "stay put" and that the time for evacuation and relocation was over. Con Edison, the power company, has also shut down power in parts of lower Manhattan to lessen damage from flooding sea waters.
New Jersey's famously blunt Gov. Chris Christie also issued a warning to those who didn't evacuate as ordered. "For those who are on the barrier islands who decided it was a better idea to wait this out than to evacuate, for those elected officials who decided to ignore my admonition, this is now your responsibility," he said Monday evening.
"If you're still able to hear me, we need you to hunker down and get to the highest point possible in the dwelling that you are in. We will not be able to come help you until daylight tomorrow."
More than a million customers already were without power by early evening Monday and millions more could lose electricity. One disaster forecasting company predicted economic losses could ultimately reach $20 billion, only half of it insured.
All U.S. stock markets were closed on Monday and will remain closed on Tuesday, according to a NYSE Euronext statement. This marks the first weather-related closure for the markets in 27 years.
The company plans to re-open the markets on Wednesday "conditions permitting" and will provide further updates on Tuesday.
The hurricane-force winds blew over a construction crane on top of a luxury high-rise building in Manhattan, leaving the crane dangling off the edge of the building. The incident, at a building called One57 on West 57th Street, prompted a huge emergency response. New York City officials ordered people in neighboring buildings to move to lower floors.
The building is known as one of the priciest ever in New York. A six-bedroom penthouse at the building is under contract for a reported $90 million. The building recently made headlines for tax breaks from a program aimed at low-income housing. (Read more: Billionaires Get 'Low-Income' Tax Breaks in Condo Tower)
The superstorm could endanger 50 million people in the most heavily populated corridor in the nation, with forecasters warning that the New York area could get the worst of it — an 11-foot wall of water.
State governors warned of the acute danger from the winds and torrential rains.
"There will undoubtedly be some deaths that are caused by the intensity of this storm, by the floods, by the tidal surge, by the waves. The more responsibly citizens act, the fewer people will die," Maryland Governor Martin O'Malley told reporters.
He added that the storm's impact on the state will be much more severe than previously thought just 24 hours ago.
President Barack Obama declared emergencies in several states including Massachusetts, Connecticut, Rhode Island, New York, New Jersey, and Pennsylvania, authorizing federal relief work to begin well ahead of time. He promised the government would "respond big and respond fast" to states and cities after the storm hits.
"My message to the governors as well as to the mayors is anything they need, we will be there, and we will cut through red tape," Obama said. "We are not going to get bogged down with a lot of rules."
Forecasting services indicated early Monday the center of the storm would strike the New Jersey shore near Atlantic City on Monday night. While Sandy does not pack the punch of Hurricane Katrina, which devastated New Orleans in 2005, it could become more potent as it approaches the U.S. coast.
"The time for preparing and talking is about over," Federal Emergency Management Administrator Craig Fugate said as Hurricane Sandy made its way up the Atlantic on a collision course with two other weather systems that could turn it into one of the most fearsome storms on record in the U.S. "People need to be acting now."
Airlines canceled more than 7,200 flights and Amtrak began suspending train service across the Northeast. New York, Philadelphia, Washington, and Baltimore moved to shut down their subways, buses and trains, and said schools would be closed on Monday. Boston also called off school. And all non-essential government offices closed in the nation's capital.
The second-largest oil refinery on the East Coast, Phillips 66's 238,000 barrel per day Bayway plant in Linden, N.J., was shutting down and three other plants cut output as the storm affected operations at two-thirds of the region's plants.
Oil prices slipped on Monday, with Brent crude near $109 a barrel. "With refineries cutting runs, we're likely to see a build-up in crude stocks which could be driving bearish prices at the moment," said Michael Creed, an economist at National Australia Bank in Melbourne.
As rain from the leading edges of the monster hurricane began to fall over the Northeast, hundreds of thousands of people from Maryland to Connecticut were ordered to evacuate low-lying coastal areas, including 375,000 in lower Manhattan and other parts of New York City, 50,000 in Delaware and 30,000 in Atlantic City, N.J., where the city's 12 casinos were forced to shut down for only the fourth time ever.
"We were told to get the heck out. I was going to stay, but it's better to be safe than sorry," said Hugh Phillips, who was one of the first in line when a Red Cross shelter in Lewes, Del., opened at noon.
"I think this one's going to do us in," said Mark Palazzolo, who boarded up his bait-and-tackle shop in Point Pleasant Beach, N.J., with the same wood he used in past storms, crossing out the names of Hurricanes Isaac and Irene and spray-painting "Sandy" next to them. "I got a call from a friend of mine from Florida last night who said, 'Mark, get out! If it's not the storm, it'll be the aftermath. People are going to be fighting in the streets over gasoline and food.'"
Authorities warned that the nation's biggest city could get hit with a surge of seawater that could swamp parts of lower Manhattan, flood subway tunnels, and cripple the network of electrical and communications lines that are vital to the nation's financial center.
On Monday, New York Governor Andrew Cuomo said New York City's Brooklyn Battery and Holland Tunnels would close at 2 p.m., while the Verrazano Bridge and George Washington Bridge would close close at 7 p.m.
Sandy, a Category 1 hurricane, was blamed for 69 deaths in the Caribbean before it began traveling northward, parallel to the Eastern Seaboard. As of 11 a.m., it was moving at 18 mph, with hurricane-force winds extending an extraordinary 175 miles from its center.
It was expected to hook inland during the day Monday, colliding with a wintry storm moving in from the west and cold air streaming down from the Arctic.
Forecasters said Sandy was a rare, hybrid "super storm" created by an Arctic jet stream wrapping itself around a tropical storm, possibly causing up to 12 inches of rain in some areas, as well as up to 3 feet of snowfall in the Appalachian Mountains from West Virginia to Kentucky, and widespread power outages that last for days.
Louis Uccellini of the National Oceanic and Atmospheric Administration told The Associated Press that given Sandy's east-to-west track into New Jersey, the worst of the storm surge could be just to the north, in New York City, on Long Island, N.Y., and in northern New Jersey.
"This is the worst-case scenario," Uccellini said.
Forecasters said that because of giant waves and high tides made worse by a full moon, the metropolitan area of about 20 million people could get hit with an 11-foot wall of water.
New York called off school Monday for the city's 1.1 million students and announced it would suspend all train, bus and subway service Sunday night. More than 5 million riders a day depend on the transit system.
Officials also postponed Monday's reopening of the Statue of Liberty, which had been closed for a year for $30 million in renovations.
President Obama also pleaded for neighborliness: "In times like this, one of the things that Americans do is we pull together and we help out one another And so, there may be elderly populations in your area. Check on your neighbor, check on your friend. Make sure that they are prepared. If we do, then we're going to get through this storm just fine."
The storm forced Obama and Republican Mitt Romney to call off their campaign events at the very height of the presidential race, with just over a week to go before Election Day. And early voting was canceled Monday in Maryland and Washington, D.C.
Despite the dire warnings, some souls were refusing to budge.
Jonas Clark of Manchester Township, N.J. — right in the area where Sandy was projected to come ashore — stood outside a convenience store, calmly sipping a coffee and wondering why people were working themselves "into a tizzy."
"I've seen a lot of major storms in my time, and there's nothing you can do but take reasonable precautions and ride out things the best you can," said Clark, 73. "Nature's going to what it's going to do. It's great that there's so much information out there about what you can do to protect yourself and your home, but it all boils down basically to 'use your common sense."'
In New Jersey, Denise Faulkner and her boyfriend showed up at the Atlantic City Convention Center with her 7-month-old daughter and two sons, ages 3 and 12, thinking there was a shelter there. She was dismayed to learn that it was just a gathering point for buses to somewhere else. Last year, they were out of their home for two days because of Hurricane Irene.
"I'm real overwhelmed," she said as baby Zahiriah, wrapped in a pink blanket with embroidered elephants, slept in a car seat. "We're at it again. Last year we had to do it. This year we have to do it. And you have to be around all sorts of people — strangers. It's a bit much."
Before leaving their home in Atlantic City, John and Robshima Williams of packed their kids' Halloween costumes so they could go bunk-to-bunk trick-or-treating at a shelter. Her 8-year-old twins are going as the Grim Reaper and a zombie, while her 6-year-old plans to dress as a witch.
"We're just trying to make a bad situation good," the mother said. "We're going to make it fun no matter where we are."