Extreme weather pattern to divide nation next week

Four seasons of weather and some of their most acute extremes may divide the nation next week.Between late Monday and Wednesday, computer models show the potential for a powerhouse storm in the middle of the nation that could unleash a dangerous outbreak of severe weather and flooding.The nation will become split by temperature contrasts as the storm draws unseasonably warm and humid air into the South while pulling abnormally cold air on its backside into the Rockies and western Plains.The spec