A significant winter storm, the most severe in over ten years, is set to affect tens of millions across the United States as it moves eastward. Fueled by the polar vortex, regions unaccustomed to such cold, including Mississippi and Florida, are warned of dangerous conditions. Forecasts indicate snow accumulations exceeding 8 inches in parts of the Midwest and temperatures dropping to historic lows. Major cities like Washington DC and Philadelphia are prepared for ice and snow as airlines announce fee waivers for disrupted travel.