ap909056286951Cities big and small along the Philadelphia-to-Boston corridor of more than 35 million people began shutting down and bundling up Tuesday against a powerful and potentially historic storm that could unload 1 to 3 feet of snow. Officials urged residents to stay safe and prepare early as the region’s transportation systems prepared to grind to a halt. Numerous utility companies warned that power could get knocked out to thousands due to high winds and heavy snow. Four states — New York, New Jersey, Connecticut and Massachusetts — have declared a state of emergency, hours before the worst of the storm hit large metropolitan areas. Forecasters said the storm would build into a blizzard, and the brunt of it would hit Monday evening and into Tuesday.  Some 7,000 flights through Wednesday have been canceled, schools and businesses closed early, and cities mobilized snowplows and salt spreaders, as they dealt with a dangerously windy blast that could instantly make up for what has been a largely snow-free winter in the urban Northeast. Amtrak has suspended service in the Northeast Corridor for Tuesday between New York and Boston and is reducing service between New York and Washington, according to a statement. More