The eastern Gulf Coast was expected to get the worst of the storms. Isolated tornadoes were possible and large hail likely north of the Florida Panhandle.
Rain creeping up the coast was primarily forecast across the Mid-Atlantic, but it was expected to freeze by the time it reaches New Jersey.
A couple of inches of snow was possible there, while New England could get as much as half a foot.
Wet weather was expected to linger in the West. Snow was forecast throughout the Rockies and Cascades, while rain was likely to fall along the West Coast.
Temperatures in the Lower 48 states Thursday ranged from minus 31 degrees at Land O' Lakes, Wis., to 91 degrees at Laredo, Texas.
