HARTFORD, Conn. (AP) — Residents across a huge swath of the U.S. were hunkered down as a massive winter storm packing snow, ice and high winds, followed by possible record-breaking cold, moved up the Eastern Seaboard, with the worst conditions expected from the Carolinas to Maine.

The massive storm expected on Thursday began two days ago in the Gulf of Mexico, first hitting the Florida Panhandle. It has prompted thousands of canceled flights, shuttered schools and businesses and sparked fears of coastal flooding and power outages.

Wind gusts of 50 mph to 60 mph, strong enough to cause downed trees and power lines, are predicted in places where the National Weather Service has issued blizzard warnings. They include the Delmarva Peninsula, which includes parts of Delaware, Virginia and Maryland; coastal New Jersey; eastern Long Island, New York; and coastal eastern New England.

Winter storm warnings stretched as far south as South Carolina on Wednesday night, but National Weather Service meteorologist Dan Peterson said the storm should be over by early Thursday in the southern states. For most of Thursday, he said, the storm will impact the Northeast, with Boston possibly getting up to 14 inches of snow.

The storm will then be followed by a wave of bracing cold.

“We think there are going to be scattered records broken for low temperatures,” said Peterson, adding how the weather service expects 28 major cities across New England, eastern New York and the mid-Atlantic states will have record low temperatures by dawn on Sunday.

State and local officials urged residents to prepare for possible power losses and stay home so crews can clear streets and roads of what could be as much as foot or more of snow in some places.

There were concerns in Boston and elsewhere that if roads aren’t properly cleared, they could freeze into cementlike icy messes by Friday, given the expected low temperatures. In other areas, plummeting temperatures already have caused water mains to burst.