A powerful winter storm brought heavy snow and icy conditions to parts of the U.S. South on Thursday, forcing officials to close schools, cancel flights and warn residents in some of the worst-hit areas to stay off roads as it lumbered eastward through Oklahoma and Texas.

A developing winter storm is threatening to drop snow, sleet and freezing rain on parts of Texas, Oklahoma and Arkansas

Texas refineries are bracing for an onslaught of cold, snow and freezing rain as the US South’s first major winter storm sweeps in during what’s projected to be a frigid month.