(CNN) Significant tornadoes are likely Thursday afternoon and evening as a storm system develops across the central United States.

"Strong winds extending through different levels of the atmosphere will make these thunderstorms capable of producing tornadoes, and therefore the tornado risk is particularly high today," CNN meteorologist Brandon Miller says. "Especially near the Mississippi and Ohio River confluence in western Kentucky and southern Illinois."

The Storm Prediction Center issued an enhanced risk, level 3 of 5 threat for severe storms for more than 3 million people in Kentucky, Illinois and Ohio.

"Severe thunderstorms with tornadoes, large hail and wind damage are likely across parts of the mid-Mississippi, Ohio and Tennessee Valleys this afternoon and evening," the Storm Prediction Center forecast Thursday morning.

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