10/28/2012 12:24 EDT | Updated 12/28/2012 05:12 EST

Hurricane Sandy Treks Parallel Up U.S. Southeast Coast

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AT SEA - OCTOBER 28: In this handout GOES satellite image provided by NASA, Hurricane Sandy, pictured at 1410 UTC, churns off the east coast on October 28, 2012 in the Atlantic Ocean. As states of emergency are declared, Sandy which has already claimed over 50 lives in the Caribbean is predicted to bring heavy winds and floodwaters to the mid-atlantic region. (Photo by NASA via Getty Images)

The mayor of New York City ordered the mandatory evacuation of hundreds of thousands of residents as Hurricane Sandy roars towards the east coast of the U.S. and parts of Canada, bringing punishing winds, heavy rainfall and storm surges.

At a press conference Sunday, Michael Bloomberg said some 375,000 people in a number of coastal areas including Coney Island, lower Manhattan and parts of the Queens neighbourhood would need to leave their homes. He said those affected would have to stay with family and friends outside of the evacuation area or at one of the 72 shelters the city has set up.

Officials in New York have also ordered the closure of its public transportation system, beginning at 7 p.m. ET on Sunday, causing problems for those trying to leave the affected area on buses and subways.

"There really is a timeline when if you don’t get there before they stop, you’re going to have to find other ways to get out," Bloomberg said. He added that those who stay behind are putting their own lives at risk as well as those of any emergency personnel if they need to enter the affected areas.

Shutting down

Schools in New York will also be closed on Monday.

Tens of thousands of people were also ordered to evacuate coastal areas across the northeastern United States, including in New Jersey and Connecticut, as officials opened shelters to house the displaced. Some 50,000 people in Delaware were told to leave their homes by 8 p.m. ET Sunday.

The New York Stock Exchange will close its trading floor Monday as Hurricane Sandy barrels its way up the Northeast, but Big Board trading will continue electronically.

NYSE Euronext said Sunday it is putting in place its contingency plans beginning Monday and will announce later when the trading floor will reopen.

Since the Great Depression, the longest suspension in trading at the NYSE occurred after the attacks on the World Trade Center on Sept. 11, 2001, when the exchange closed for four days.

The United Nations offices in New York will close on Monday and all meetings at the UN headquarters have been cancelled until Tuesday.

Amtrak began cancelling train service Saturday night to parts of the East Coast and planned to suspend nearly all service in the Northeast by Monday night.

Airlines started moving planes out of airports to avoid damage and added Sunday flights out of New York and Washington in preparation for flight cancellations on Monday. Airports along the Eastern Seaboard have cancelled thousands of flights through Wednesday.

The Virginia National Guard was authorized to call up to 500 troops to active duty for debris removal and road-clearing, while homeowners stacked sandbags at their front doors in coastal towns.

An emergency declaration will force the shutdown of Atlantic City's 12 casinos for only the fourth time in the 34-year history of legalized gambling there. City officials said they would begin evacuating the gambling hub's 30,000 residents at noon Sunday, busing them to mainland shelters and schools.

Canadian officials, meanwhile, are urging those in the path of Hurricane Sandy to be prepared.

The system was centred about 440 kilometres southeast of Cape Hatteras, N.C., according to an update from Environment Canada at 8 a.m. ET. Hurricane Sandy — rated as a Category 1 storm — had 120 km/h sustained winds and was heading northeast at 22 km/h. Little change in strength in the large storm is expected while it remains offshore.

Red Cross advises residents to prepare

The weather agency said the storm is expected to hit Ontario, Quebec and the Maritimes later Monday or early Tuesday as a post-tropical storm with heavy rainfall, winds and waves.

Environment Canada said heavy rainfall was expected in parts of Ontario and Quebec beginning late Monday or early Tuesday, although the amount would vary greatly according to location. Some regions could see up to 75 millimetres.

The Canadian Hurricane Centre says parts of southern Ontario should brace for 100 km/h winds, especially along western Lake Ontario. Environment Canada said strong winds with gusts exceeding 90 km/h could also batter parts of Quebec.

The Maritimes will also experience some rainfall and strong winds, as well as large waves and pounding surf.

The Canadian Red Cross issued a statement Sunday urging people to prepare for the storm by stocking a number of supplies including water, food, flashlights and a first aid kit. Hurricane Sandy could down trees and power lines and cause flooding, the organization said.

"Be prepared to take care of yourself and your family for at least 72 hours in an emergency,” Mike Morton, the Canadian Red Cross director of disaster management in Ontario, said in a release. “By taking some time now to store emergency food, water and other supplies, you can provide for your entire family during a power outage or evacuation."

Hurricane Sandy was headed north from the Caribbean, where it left nearly five dozen dead. It's forecast to meet a winter storm and a cold front, plus high tides from a full moon. Experts said the rare hybrid storm is expected to cause havoc over 1,300 kilometres from the East Coast to the Great Lakes.

The storm was so big, however, and the convergence of the three storms so rare, that "we just can't pinpoint who is going to get the worst of it," said Rick Knabb, director of the U.S. National Hurricane Center in Miami.

Forecasters say tropical storm conditions are spreading over North Carolina's coastline and gale-force winds should hit portions of the mid-Atlantic coast later Sunday, with higher winds likely to follow.

States of emergency were declared from North Carolina, where steady rains were whipped by gusting winds Saturday night, to Connecticut. Delaware ordered mandatory evacuations for coastal communities by 8 p.m. Sunday.

Pay attention to updates

Environment Canada said wind speeds in excess of 100 km/h were possible in southern Ontario, which could down tree branches and possibly uproot trees. Strong winds could also batter Quebec.

The organization suggested those in the affected areas should pay attention to updates, as the track of the storm could change.

"There are still various factors that could influence the evolution of the storm and there is still some degree of uncertainty with respect to the magnitude of the potential impact," it said in a statement.

The White House said U.S. President Barack Obama is cancelling campaign appearances in Northern Virginia on Monday and Colorado on Tuesday so he can monitor Hurricane Sandy. The storm is currently forecast to make landfall along the Eastern Seaboard at that time.

At the headquarters of the Federal Emergency Management Agency in Washington, D.C., Obama said the storm's path is uncertain so officials can't predict where it will make landfall or where it will have the greatest impact.

"That’s exactly why it’s so important for us to respond big and to respond fast as local information starts coming in," he said.

Obama also said Hurricane Sandy is unique because it is large and slow moving, which means it could take some time for cleanup crews to repair any damage.

"My main message to everybody involved is that we have to take this seriously," he said.

Instead of campaigning in Virginia as scheduled, Republican challenger Mitt Romney was set to join running mate Paul Ryan for several campaign stops in Ohio.

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