It’s a strange forecast for the last travel weekend before the holiday: dangerous ice in the Northeast and Midwest, the risk of a rare December tornado across parts of the South and for the East Coast, a blast of balmy temperatures. For people caught in the worst of it, it will mean “a lot of misery,” said Michael Palmer, a lead meteorologist at The Weather Channel. Chicago and Detroit were already experiencing icy conditions early Friday, and a band of light snow hitting parts of the central Great Plains and western Great Lakes is set to increase over the weekend, dumping up to 10 inches of snow on Kansas City and Milwaukee. Northern New England is bracing for icy conditions Saturday into Sunday, while parts of the South were bracing for the threat of strong tornadoes on Saturday — officially the first day of winter. The danger zone includes eastern Texas, northern Louisiana, Arkansas and western Mississippi.