Hurricane Sandy takes aim at Eastern Seaboard

Interactive: Hurricane Tracker (on this page) Hurricane Sandy closed in on the United States Sunday as coastal communities along the East Coast scrambled to prepare for torrential rains, high winds, major flooding, power outages and heavy snow a week before the presidential election. Forecasters said Sandy has the ingredients to transform into a "super storm" as it merges with an Arctic jet stream, which could make the storm unlike anything seen over the eastern United States in decades. "We're looking at impact of greater than 50 to 60 million people," said Louis Uccellini, head of environmental prediction for the National Oceanic and Atmospheric Administration. States of emergency were declared in eight states from North Carolina to Massachusetts, as well as Washington, D.C., as Sandy made its way north after killing 41 people in the Caribbean. Governors of states in Sandy's path and New York City's Mayor Michael Bloomberg ordered mandatory evacuations of vulnerable areas.New York Gov. Andrew Cuomo also ordered New York City's subway, bus and commuter railroads to shut down , beginning at 7 p.m. ET Sunday. In an 8 a.m. Sunday advisory, the National Hurricane Center said Sandy was about 260 miles southeast of Cape Hatteras, N.C., and was moving northeast at 10 mph, down from 14 mph Saturday night "Gale force winds are expected to arrive along portions of the Mid-Atlantic coast later today," reaching Long Island and southern New England by Monday morning, it said. "The combination of an extremely dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters." It said could occur in parts of North Carolina, Virginia, Maryland, Connecticut, Rhode Island and New York. Forecasters said Sandy could make U.S. landfall anywhere between Maryland and southern New England, forecasters said. Some computer models show a likely landfall between Delaware and the New York/New Jersey area. Sandy's winds were not overwhelming for a hurricane -- sustained at 75 mph Sunday morning with higher gusts. But its width is exceptional. Hurricane force winds extended 105 miles from its center while its lesser tropical storm-force winds reached across 700 miles. Sandy could be the largest storm ever to hit the United States, according to the National Oceanic and Atmospheric Administration's website. Slideshow: Sandy sets sights on East Coast (on this page) "The size of this alone, affecting a heavily populated area, is going to be history making," said Jeff Masters, a hurricane specialist who writes a blog posted on the Weather Underground. Slideshow: Sandy sets sights on East Coast (on this page) Officials urged residents to stock up on food, water and batteries. Worried residents packed stores throughout the region, buying groceries, generators, candles, and other supplies in anticipation of power outages. Some local governments announced schools would be closed on Monday and Tuesday. As the threat of a monster storm began to sink in, shoppers crowded hardware stores and supermarkets looking to stock up on emergency supplies. . Sandy also was disrupting travel in the region. As of Sunday morning, more than 3,200 flights had been canceled. Rail service also was impacted. Story: Sandy could mean travel trouble President Barack Obama on Sunday was to will visit the National Response Coordination Center at FEMA Headquarters, where deployment of federal resources and teams to states up and down the East Coast will be coordinated, the White House said. On Saturday was briefed by  Homeland Security Secretary Janet Napolitano, FEMA Administrator Craig Fugate and other officials. FEMA is preparing water, meals, blankets and other resources should they be needed at support bases along the East Coast, the White House said. "Get somewhere safe and stay there during the storm, and then teams will get out as soon as they can and start checking on things," Fugate told The Weather Channel on Sunday. "But it really helps if people evacuate ahead of time, that way teams aren't having to go out and do rescues. They can focus on recovery, because people went somewhere safe." Coastal flooding posed a major threat, particularly in low-lying areas like New York City, the global financial nerve center, and Alexandria, Va., across the Potomac River from Washington, D.C. "This is not a coastal threat alone," Fugate told reporters, warning of the potential for flooding in Maryland and Pennsylvania, as well as more than 2 feet of snow in West Virginia and southwest Pennsylvania. "This is going to go well inland," he added. Forecasters: Sandy 'one for record books' Mandatory evacuations New York City Mayor Bloomberg ordered mandatory evacuation of 370,000 people from low-lying areas in New York City, signifying officials' growing concern about the severity of the storm and its impact on the five boroughs. The city opened 65 shelters in public schools on Sunday morning and said more could be opened. Last year, the mayor called for an evacuation in anticipation of Tropical Storm Irene, which officials called unprecedented. Bloomberg also said the city's public schools would be closed on Monday. Delaware Governor Jack Markell ordered a mandatory evacuation of an estimated 50,000 people in coastal communities. New Jersey's Cape May County ordered an evacuation of its barrier islands, home to some popular beach resorts, by Sunday afternoon. Video: Carolinas, East Coast on watch for Hurricane Sandy Election issues Coming in the hectic run-up to the U.S. presidential election on Nov. 6, the storm presented a challenge to the campaigns of Obama and his Republican challenger, Mitt Romney. Obama is canceling campaign stops in Virginia and Colorado early next week because of the hurricane and will instead monitor the storm from the White House, his spokesman said Saturday. Romney rescheduled his campaign events for Virginia on Sunday and was flying to Ohio instead. Sandy is set to deliver potential election surprise Power outages caused by the storm could continue through the election, NBC meteorologist Bill Karins warned. "After the storm hits, expect the clean-up and power outage restoration to continue right up through Election Day," Karins said. "Serious and life-threatening weather conditions are expected from Outer Banks to New England." Share your images of Hurricane Sandy preparationsVideo: Carolinas, East Coast on watch for Hurricane Sandy Although Sandy is not forecast to be as strong as other recent storms to hit the Northeast -- such as Hurricane Irene in August 2011, which left $4 billion in damage -- it holds the potential to cause significant damage because it will be moving slowly. Some experts predict at least $1 billion in damage in the United States. BreakingNews.com's coverage of Sandy Tips on preparing for Sandy Story: Busy Atlantic storm season tied to lack of El Nino "This is going to make this left-hand turn, and when a cyclone takes a completely different track, that increases the chances beyond what would have already been there for different spots that did or didn't experience flooding and other impacts during Irene to have a different outcome this time," NHC director Rick Knabb told The Weather Channel early Sunday. "So you have to prepare as if you've never experienced this one before, because you haven't." NBC News' Ian Johnston, Miranda Leitsinger, Miguel Llanos, Andrew Mach and Jim Gold, The Associated Press and Reuters contributed to this report.