The US urged 55mn people on its East Coast yesterday to prepare for the onslaught of massive Hurricane Irene, which President Barack Obama warned could be “extremely dangerous and costly.”“All indications point to this being a historic hurricane,” Obama said, as Irene, a wide storm packing winds of more than 160kph, bore down on the North Carolina coast for an expected landfall today.President Obama also cut short his vacation and was heading back to the White House yesterday, before Hurricane Irene hits the US East Coast, the White House said.“In the mind of the president, he felt it was prudent for him to be at the White House this evening,” said White House spokesman Josh Earnest. Obama had been scheduled to end his nine-day family vacation today morning.But Obama, who had already been criticised for taking a holiday on this upscale island while US unemployment remains above 9%, decided getting back to the White House early was wise.The president had already been taking great care to appear that he is on top of storm preparation during his holiday.Obama has held regular conference calls on the storm with aides in a determined effort to learn from the mistakes of his predecessor George W Bush, who was slammed for an ineffectual response after Hurricane Katrina swamped New Orleans in 2005.Earnest said the travel plans for the president’s wife Michelle and their two daughters was unclear. He had initially said they would stay on Martha’s Vineyard until today as planned.Forecasters expect the menacing, broad hurricane to rake up the densely populated US eastern seaboard starting on Saturday, then extend on Sunday to New York, America’s most populous city with more than 8mn residents, and then into New England.“The wind field is huge,” US National Hurricane Center (NHC) Director Bill Read said.The NHC said hurricane force winds extended outward up to 150km from Irene’s center, while tropical storm force winds extended out to 465km, giving the storm a vast wind field width of nearly 960km.US federal and state leaders, from Obama downward, urged the millions of Americans in the hurricane’s path to prepare and to heed evacuation orders if they received them.“If you are in the projected path of this hurricane, you have to take precautions now .... don’t wait, don’t delay,” Obama said, speaking from the island of Martha’s Vineyard off the Massachusetts coast where he is vacationing.“We all hope for the best but we have to be prepared for the worst,” Obama added.In earlier comments, NHC chief Read said Irene, which will be the first significant hurricane to affect the populous US Northeast in decades, would lash the eastern seaboard with tropical storm-force winds and a “huge swath of rain” from the Carolinas to New England.He said North Carolina would start seeing tropical storm conditions on Friday afternoon. Cities like Washington, Baltimore, Philadelphia and New York could experience heavy rain and wind and and power outages from the weekend.Irene weakened early yesterday to a Category 2 hurricane from a 3 on the five-step Saffir-Simpson scale, but it still was carrying winds of up to 165kph.At 11am (1500 GMT), its center was churning north 530km south-southwest of Cape Hatteras, North Carolina.The Miami-based hurricane center suggested yesterday Irene may already have peaked during its passage over the Bahamas, when its wind speeds made it a Category 3 “major” hurricane.But it could still roar up the eastern seaboard as a broad and dangerous Category 2.Coastal communities from the Carolinas to New England stocked up on food and water and tried to secure homes, vehicles and boats. States, cities, ports, hospitals, oil refineries and nuclear plants activated emergency plans.“We’ve been through about four or five (hurricanes), but this looks like it’ll be the worst,” Henry Burke, a vacation homeowner in Atlantic Beach, North Carolina, said.US Homeland Security Secretary Janet Napolitano urged residents not to delay precautions. “The window of preparation is quickly closing,” Napolitano said.“This is a big, bad storm,” North Carolina Governor Bev Perdue told CNN.Maryland Governor Martin O’Malley told the TV network: “Anyone who thinks this is just a normal hurricane and they can stick it out is being ... selfish and stupid.”The US capital, Washington, was also expected to feel heavy wind and rain. Federal Emergency Management Agency (FEMA) chief Craig Fugate warned millions on the seaboard to expect power outages “for days”, flash-flooding and strong winds. Reuters