At least five people are dead including two children after a string of violent storms slammed several communities from Texas to Mississippi.
The deadly storm system is now moving East and threatening about 80 million people from Ohio to New York.
It moves the risk of life-threatening winds, strong tornadoes and large hail to a heavy populated section of the U.S.
Meteorologists are concerned the storm will continue its destructive pattern.
In Texas, two children ages 3 and 8 were killed when a tree fell on their car.
In another incident,a woman died after her mobile home was destroyed.
The National Weather Service says a likely tornado with winds up to 140 miles-per-hour touched down in Robertson County, Texas.
Meanwhile, in Louisiana, the storms also claimed the life of a 13 year old boy who drowned in a drainage area.
Mississippi emergency officials report at least one death in the town of Hamilton.