Forecasters say severe storms could bring flash flooding, large hail and tornadoes to parts of the deep South.
The national Storm Prediction Center says more than 40 million people in several states - including Texas, Oklahoma, Arkansas, Louisiana and Mississippi - will be at risk for severe storms Wednesday.
In Mississippi, forecasters say 3-4 inches of rain will be likely in storms Wednesday into Thursday, which could lead to flash flooding.
The Storm Prediction Center says that many large cities will be at risk of severe storms Wednesday, including Dallas, Oklahoma City, Kansas City and New Orleans.
Heavy rain is then expected to begin falling in Alabama, Tennessee and Georgia as the system moves east. In Atlanta, forecasters are calling for heavy rain beginning Wednesday night.