Additional heavy rain is expected across the Plains this week. With streams already swollen and the ground saturated, that leaves the area at risk of additional flooding.
The relentless series of storms caused deaths or damage from the Plains to Canada to New England. Hundreds of thousands of people lost power and air conditioning during days of sweltering heat.
Multiple people died Tuesday and at least a dozen were injured when a powerful tornado tore through a small Iowa town, carving a bleak landscape of destroyed homes, shredded trees and smashed cars.
Forecasters warned a wave of dangerous storms in the U.S. could march through parts of the South early Thursday, after deadly storms a day earlier spawned damaging tornadoes and massive hail.
The storm caused deaths and damage in the Southeast and stranded motorists on highways in the Midwest. It is expected to bring heavy rain to the Northeast, parts of which got a foot of snow on Sunday.
Police and firefighters in Clarksville were responding to multiple reports of damage in the northern part of the city, which is located north of Nashville near the Kentucky state line.
A tornado touched down Wednesday evening near Chicago's O'Hare International Airport, prompting passengers to take shelter and disrupting hundreds of flights. There were no reports of injuries.
A large tornado hit southeastern Missouri before dawn, causing widespread destruction as a broad swath of the Midwest and South braced for further storms that could spawn additional twisters and hail.
The powerful storm system spread destruction in several states. In Illinois, one person died and 28 were hurt after a theater roof caved in during a concert.