It was expected to hook inland during the day Monday, colliding with a wintry storm moving in from the west and cold air streaming down from the Arctic.Forecasters said the combination could bring close to a foot of rain in places, a potentially lethal storm surge of 4 to 11 feet across much of the region, and punishing winds that could cause widespread power outages that last for days. The storm could also dump up to 2 feet of snow in Kentucky, North Carolina and West Virginia. Louis Uccellini, environmental prediction chief for the National Oceanic and Atmospheric Administration, told The Associated Press that given Sandy's east-to-west track into New Jersey, the worst of the storm surge could be just to the north, in New York City, on Long Island and in northern New Jersey. Forecasters said that because of giant waves and high tides made worse by a full moon, the metropolitan area of about 20 million people could get hit with an 11-foot wall of water. "This is the worst-case scenario," Uccellini said. New York Mayor Michael Bloomberg warned: "If you don't evacuate, you are not only endangering your life, you are also endangering the lives of the first responders who are going in to rescue you. This is a serious and dangerous storm." New Jersey's famously blunt Gov. Chris Christie was less polite: "Don't be stupid. Get out." New York called off school Monday for the city's 1.1 million students and shut down all train, bus and subway service Sunday night. More than 5 million riders a day depend on the transit system. Officials also postponed Monday's reopening of the Statue of Liberty, which had been closed for a year for $30 million in renovations. The United Nations said it would close Monday and canceled all meetings at its headquarters.