The same system that brought deadly tornadoes and complete devastation to Oklahoma is on the move Thursday. 

'DAMAGING' TORNADOES SWEEP THROUGH OKLAHOMA, LEAVING AT LEAST 2 DEAD

It is crossing over the Mississippi and Tennessee valleys, with the risk of very large hail, damaging winds, tornadoes and flooding rainfall.

Behind this system, the air is cold enough for upward of a foot of snow from the Great Lakes back through the Rockies.

Ahead of the storm, temperatures are very warm, which will enhance the threat of strong thunderstorms throughout the day.

Meanwhile, the Northwest and northern California remain unsettled, with more coastal rain and snow in the higher elevations.