A massive winter storm system has unleashed dangerous blizzard conditions in parts of the central United States, shutting down highways and stranding drivers in frigid temperatures Monday, and it’s pummeling parts of the South with hail storms, heavy flooding and tornado threats.

The fast-moving storm is making its way east and will cover over 1,800 miles in 72 hours, producing notable snowfall across more than half a dozen states.

The system strengthened as it tracked out of the Four Corners region – where it dumped snow that brought some travel to a halt Sunday – and into the southern Plains Monday afternoon.

By Monday evening, heavy snow and powerful winds stretched from the Texas Panhandle to Nebraska, where authorities had already responded to dozens of weather related-incidents on the road and urged residents not to travel because of the dangerous whiteout conditions.