A prolonged period of heavy rainfall is expected to hit the southern U.S. this week. Roughly 10 million people across areas of Mississippi, Tennessee, Alabama, and Georgia will be affected.

The rain is forecasted for early Monday and will continue into Tuesday and could bring several inches of rainfall across the week. Showers, thunderstorms and wind are forecasted for cities like Nashville and Atlanta.

"A prolonged rainfall event is expected across the Mississippi/Tennessee Valleys beginning Monday and extending into the weekend, as multiple waves of rainfall sweep eastward along a stalled frontal boundary," the National Weather Service tweeted Saturday.

"A swath of 3-5" totals are forecast through Friday, w/ locally higher amounts possible," it added.

The rain is expected to hit the hardest in Mississippi and Tennessee, which have been experiencing dry conditions recently with drought levels at 1 to 2.

The heavy rainfall has drawn concerns about possible flooding. In 2010, Tennessee saw more than $2 billion in damages from severe flooding.

"There certainly is potential for isolated to widely scattered amounts over 3 inches, which certainly could pose a flooding threat," NWS said.