At a Glance Areas of snow, sleet and freezing rain are possible from the South to the Midwest and East.Colder weather will spread into parts of the U.S. early this week.The cold will be most persistent from the northern Rockies into parts of the Plains and upper Midwest. Sign up for the Morning Brief email newsletterto get weekday updates from The Weather Channel and our meteorologists. A​n arctic cold snap plunged into the middle of the country over the weekend,...