Forecasters warned of life-threatening flash flooding as a stalling system brings days of heavy rain and a tornado threat across much of the country.

Intense thunderstorms are expected to unleash rounds of heavy rain that could bring dangerous flooding to tens of millions of people in the central and eastern US this week.

For now, strong storms are expected to stay mainly in northern Mississippi and the mid-south, at least until the weekend.

Thunderstorms, large hail, destructive wind gusts and strong tornadoes threaten up to 73 million people across the Mississippi, Ohio and Tennessee Valleys on Sunday. By evening, Michigan, Missouri and Mississipi each had preliminary tornado reports as a storm system slowly marched east,

Forecasters issued a tornado warning for northern Harrison County and warned several cities across the region to expect severe weather Monday morning.

Forecasters are warning of potentially deadly flash flooding and strong tornadoes as more rounds of thunderstorms are poised to strike parts of the Midwest and South.

After severe weather knocked out power for thousands Monday, forecasters say possible tornadoes or otherwise damaging winds and hail are on the way.

Forecasters warned of widespread damaging winds, very large hail and tornadoes, from Texas to the East Coast starting on Sunday.