MOREHEAD CITY, North Carolina — Hurricane Irene zeroed in on land Saturday, losing some power but still threatening a catastrophic run up the East Coast as more than 2 million people were told to move to safer places to escape the massive storm. New York City ordered America's biggest subway system shut down for the first time ever because of a natural disaster. A hurricane warning was issued for the city for the first time in two decades, and more than a quarter-million people in New York were ordered to evacuate. The warning was in effect Friday from North Carolina in the south all the way to Massachusetts in the north. Officials declared emergencies, called up hundreds of National Guard troops, shut down public transit systems and begged hundreds of thousands of people to obey evacuation orders. U.S. airlines were canceling at least 6,100 flights through Monday, grounding hundreds of thousands of passengers. The storm could strike major airports from Washington to Boston with heavy rain and dangerous winds. The National Hurricane Center in Miami said the enormous storm's top sustained winds were down to 90 mph (145 kph) early Saturday from 100 mph (160 kph) overnight but warned that Irene would remain a hurricane as it moves up the mid-Atlantic coast, even after losing some more strength once it hits land. "The hazards are still the same," NHC hurricane specialist Mike Brennan said. "The emphasis for this storm is on its size and duration, not necessarily how strong the strongest winds are." As the storm's outermost bands of wind and rain began to lash islands off the coast of the southern state of North Carolina, authorities in points farther north begged people to get out of harm's way. President Barack Obama, speaking from Martha's Vineyard Island off the coast of Massachusetts before ending his vacation early, said all indications point to the storm being a historic hurricane. "Don't wait. Don't delay," said Obama, who decided to cut short his summer vacation by a day and return to Washington. "I cannot stress this highly enough: If you are in the projected path of this hurricane, you have to take precautions now." Senior hurricane specialist Richard Pasch of the National Hurricane Center said there were signs that the hurricane may have weakened slightly, but strong winds continued to extend 100 miles (160 kilometers) from its center. The storm's center was about 50 miles (80 kilometers) south of Cape Lookout on North Carolina's Outer Banks early Saturday and lumbering north-northeastward at 14 mph (23 kph). Sustained winds of 67 mph (108 kph), nearing the 74 mph (119 kph) threshold for a hurricane, were clocked at Cape Lookout, the National Hurricane Center said. Long before the storm's eye crossed the coastline, rain and tropical storm-force winds already were pelting North and South Carolina as Irene trudged north, snapping power lines and flooding streets. Officials warned of dangerous rip currents. Wind and rains knocked out power to about 45,000 customers along the coast, including a hospital. Irene's wrath in the Caribbean, including Puerto Rico, the Dominican Republic and the Bahamas, gave a preview of what might be coming to the U.S.: Power outages, dangerous floods and high winds that caused millions of dollars in damage. The U.S. East Coast, home to some of the country's most densely populated cities and costliest waterfront real estate, was expected to suffer a multibillion-dollar disaster. In addition to widespread wind and water damage, Irene could also push crude oil prices higher if it disrupts refineries in Delaware, New Jersey, Pennsylvania and Virginia, which produce nearly 8 percent of U.S. gasoline and diesel fuel. Forecasters warned wind-whipped water could create a dangerous storm surge, with levels along North Carolina's Albemarle and Pamlico sounds rising as much as 11 feet (3.35 meters). In Washington, Irene dashed hopes of dedicating a 30-foot (10-meter) sculpture to Martin Luther King Jr. on Sunday on the National Mall. While a direct strike on the U.S. capital appeared slim, organizers said the forecasts of wind and heavy rain made it too dangerous to summon a throng they expected to number up to 250,000. In Atlantic City, New Jersey, all 11 casinos announced plans to shut down Friday, only the third time that has happened in the 33-year history of legalized gambling in that state. New York City ordered more than 300,000 people who live in flood-prone areas to leave, including Battery Park City at the southern tip of Manhattan, Coney Island and the beachfront Rockaways. But it was not clear how many would do it, how they would get out or where they would go. Most New Yorkers don't have a car. On top of that, the city said it would shut down the subways and buses at noon Saturday, only a few hours after the first rain is expected to fall. Mayor Michael Bloomberg said there was little authorities could do to force people to leave. "We do not have the manpower to go door-to-door and drag people out of their homes," he said. "Nobody's going to get fined. Nobody's going to go to jail. But if you don't follow this, people may die." America's biggest city has not seen a hurricane in decades, and a hurricane warning hasn't been issued there since Hurricane Gloria hit in 1985 as a Category 2 storm, said Ashley Sears, a meteorologist with the National Weather Service. Even if the winds aren't strong enough to damage buildings in a metropolis made largely of brick, concrete and steel, a lot of New York's subways and other infrastructure are underground, making them subject to flooding. New York's two airports are close to the water and could be inundated, as could densely packed neighborhoods, if the storm pushes ocean water into the city's waterways, officials said. The five main New York City-area airports planned to close to arriving passenger flights beginning at noon (1700 GMT) on Saturday, aviation officials said. The Port Authority of New York and New Jersey, which operates the airports and area bridges and tunnels, said Friday that many weekend departures already had been canceled in anticipation of the hurricane. In the last 200 years, New York has seen only a few significant hurricanes. In September 1821, a hurricane raised tides by 13 feet (4 meters) in an hour and flooded all of Manhattan south of Canal Street, the southernmost tip of the city. The area now includes Wall Street and the World Trade Center memorial. An infamous 1938 storm dubbed the Long Island Express came ashore about 75 miles (120 kilometers) east of the city and then hit New England, killing 700 people and leaving 63,000 homeless. In 2008, the city had a brush with Tropical Storm Hanna, which dumped 3 inches (8 centimeters) of rain on Manhattan.
