Story highlights Heavy rainfalls of 6-10 inches are expected in North Carolina

Storms caused flash flooding in eastern Tennessee over the weekend

(CNN) The Carolinas and Mid-Atlantic states are bracing for a round of strong thunderstorms and the threat of flash flooding.

A system of storms carrying heavy rain that left hundreds of roads flooded in eastern Tennessee over the weekend is slowing moving northeast.

Flash flood watches and warnings

Nearly 6 million people are under flash flood watches and warnings as the storm slowly moves northeast, the National Weather Service said.

There's a high risk of flash flooding from Charleston, SC to Fayetteville, NC where residents could see 6 to 10 inches fall through Tuesday morning, CNN meteorologist Michael Guy said.

Some isolated areas could see even higher amounts of rain.

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