Sandy Super Storm

AMERICANS awoke to scenes of devastation after megastorm Sandy battered the East Coast, flooding parts of New York City, paralysing transport and leaving millions without electricity.

The storm weakened as it moved further inland but forecasters still warned of gale-force winds and flooding along the densely populated coast, where a massive fire broke out in New York City and a levee broke in New Jersey.

At least 35 people were killed in the US and Canada as the storm roared ashore at 8pm (11am AEDT) yesterday, pounding several major cities with heavy rain and hurricane-force winds that toppled trees and ripped down power lines.

Sandy had already killed at least 67 people - including a US national in Puerto Rico - as it swept through the Caribbean over the past few days, meaning the overall toll from the storm is now 102.

President Barack Obama declared a "major disaster" had hit the states of New York and New Jersey, an order that cleared the way for federal grants and loans to help storm victims acquire temporary housing and repair damage.

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Seawater coursed between the iconic skyscrapers of New York's financial district in lower Manhattan, flooding subways and road tunnels and shorting out the power grid, leaving a half-million households and businesses in the dark.

Subway trains and buses remained suspended for a third day and hundreds of thousands of homes face up to a week without electricity, the power company warned.

The stock exchange in what Americans call the city that never sleeps remained closed for a second day.

Further south, the sea surged over vast swaths of the eastern seaboard, turning coastal cities into ghost towns as the high winds grounded flights and shut down rail links, public transport and government offices.

The catastrophe completely overshadowed the US election race, forcing a halt to campaigning a week before Americans were due to go to the polls to choose between Mr Obama and challenger Mitt Romney.

Authorities had ordered hundreds of thousands of residents in areas from New England to North Carolina to evacuate their homes and seek shelter, but many chose to stay on, to the frustration of police and local officials.

Falling trees tore down power cables, plunging what weather experts said were millions of homes into darkness, while storm warnings cut rail links and marooned tens of thousands of travellers at airports across the region.

A nuclear power plant in New Jersey declared an alert as waters rose.

The Oyster Creek nuclear power plant, just north of Atlantic City, New Jersey, was already on a scheduled outage as Sandy made landfall, and the industry regulator said there was no immediate danger.

The hurricane sent a record storm surge of 4.15m into lower Manhattan, flooding seven major subway tunnels used by hundreds of thousands of daily commuters and swamping cars in the financial district.

The storm caused the worst damage in the 108-year history of New York's extensive subway system, according to Joseph Lhota, the chairman of the Metropolitan Transportation Authority.

"The New York City subway system is 108 years old, but it has never faced a disaster as devastating as what we experienced last night," he said last night.

Firefighters struggled to contain a massive blaze in the Queens borough that destroyed more than 50 homes, and in northern New Jersey police in boats pulled residents from second-story windows after a levee broke. Bergen County executive chief of staff Jeanne Baratta told The Record newspaper as many as 1000 people could need help in New Jersey.

Hours earlier, a power sub-station exploded in a burst of light captured by amateur photographers as a massive blackout left much of Manhattan and homes across New York City, in darkness. The flood waters had begun to recede last night, but the Consolidated Edison power company said it could take a week to completely restore power.

"This will be one for the record books," said John Miksad, senior vice-president for electric operations at Con Edison, which had more than 670,000 customers without power in and around New York City.

New York City's three major airports remained closed. Overall, according to the flight-tracking service FlightAware, more than 13,500 flights had been canceled over two days, almost all related to the storm.

Disaster estimating firm Eqecat forecast that Sandy would affect more than 60 million Americans, a fifth of the population, and cause up to $20 billion in damage.

Refineries closed and major arteries such New York's Holland Tunnel were shut to traffic. The operator of two major New Jersey nuclear plants said they might have to be closed, threatening half the state's power supply.

Trading at the New York Stock Exchange was canceled again - the first time the exchange suspended operations for two consecutive days due to weather since an 1888 blizzard struck the city. The Nasdaq and the futures markets in Chicago were closed, along with federal government offices and the entire Amtrak rail network on the eastern seaboard.

Skyscrapers swayed and creaked in winds that partially toppled a crane 74 stories above Midtown.

Chicago officials warned residents to stay away from the Lake Michigan shore as the city prepared for winds up to 96 km/h and waves exceeding 7.2m.

Mr Obama urged Americans to heed local evacuation orders as he stepped off the campaign trail and spent the day in the White House helping to co-ordinate the response to the disaster. "The election will take care of itself next week," he said. "Right now, our No 1 priority is to make sure that we are saving lives ... and that we respond as quickly as possible to get the economy back on track."

Both the Democratic incumbent and his Republican rival were keen to display resolute leadership in the face of the storm, given the memory of Hurricane Katrina in 2005.

Former president George W. Bush was widely seen as having bungled the handling of Katrina, which devastated New Orleans. The failure of authorities in the ensuing emergency response tainted the rest of his presidency.