In the most punishing blast of arctic air this season, subzero wind chill readings stretched as far south as Georgia and Alabama on Thursday as cities all over the eastern half of the country approached record low temperatures, NBC News reported. It felt like 7 below in Roanoke, Virginia, and just below freezing in Orlando, Florida Thursday morning. Cold alerts covered almost the entire country east of the Mississippi River, more than 180 million people in all. By Friday night, some cities on the eastern shores of Lake Michigan and around Buffalo and Syracuse, New York, could get a foot and a half or snow. Meanwhile, 3 people were killed on Wednesday night in an 18-car pileup in whiteout conditions on a Pennsylvania interstate.