A hurricane of enormous force marched north Saturday, poised to hammer the Eastern Seaboard as early as Monday and disrupt life for millions as it sweeps across eight states toward Canada.
From North Carolina to the coastal edges of Maine, public officials urged residents to fortify themselves against Hurricane Sandy, which is expected to unleash torrential rains and winds of up to 75 mph, even for those residing as far as 100 miles from the storm's center.
Sandy was several hundred miles southeast of Charleston, S.C., on Saturday after blowing through the Bahamas and traveling north over the Atlantic Ocean.
While Sandy's speed had declined to 75 mph, making it possible that it would lose its status as a tropical storm or hurricane, meteorologists said it would pick up force as it merges with a jet stream and a nor'easter.
Two computer tracking systems remained in agreement that the hurricane would arrive on shore between the Delaware coast and Rhode Island. But Sandy's reach will extend as far as 450 miles from its core, which prompted at least one governor, Chris Christie of New Jersey, to order evacuations of coastal areas and the state's casinos.
The impending storm disrupted the rhythms of an otherwise warm fall Saturday, as utility crews up and down the East Coast worked overtime to prepare, and hordes of anxious shoppers crowded into supermarkets and supply stores.
Federal officials said that they expected the storm to create damaging flood and wind conditions across a vast and densely populated portion of the United States, from Virginia to New England, and as far west as the Great Lakes.
"We need to make sure people understand that this is going to go well inland," Craig Fugate, the administrator for the Federal Emergency Management Agency, said in a conference call with reporters. "This is not a coastal threat alone."
FEMA officials said they were uncertain which areas would be the most ravaged. The hurricane itself is expected to lose intensity before it merges with a separate storm system in the Northeast.
Yet Sandy's breadth makes its precise path almost irrelevant.
State and federal officials, Fugate said, are planning for several days of treacherous conditions throughout the mid-Atlantic states, probably beginning Monday and perhaps extending to Thursday. Forecasters expect flash flooding from as much as 8 inches of rain. They are preparing for as much as 2 feet of snow to bury mountain areas in West Virginia, Virginia and North Carolina.
In New Jersey, Christie announced mandatory evacuation of Atlantic City casinos and barrier islands from Sandy Hook to Cape May by 4 p.m. today. He warned residents that they could be without power for as long as a week.
"We have to be prepared for the worst here," he told reporters.
James Baker, the mayor of Wilmington, Del., issued an evacuation order for the southeastern section of his city, an edict that will require some 3,000 residents to clear out before the storm strikes.
In New York, Mayor Michael Bloomberg advised residents and visitors to stay out of the parks. Construction sites were ordered shut down. Officials also prepared for a possible shutdown of the subway and regional rail system, depending on the storm's path.