A significant storm system is set to impact 40 U.S. states this mid-October, bringing a variety of weather hazards from coast to coast. The storm, driven by a dynamic jet stream and multiple low-pressure systems, will result in early-season snowfall in the Rockies and Sierra Nevada, while strong thunderstorms, some potentially severe, are expected across the Plains and Midwest. The eastern part of the storm will bring heavy rain and gusty winds to the Mississippi and Ohio valleys.