Millions of Americans across the country are on alert for a severe weather outbreak as violent, long-track tornadoes with damaging winds of up to 80 mph and large hail are expected across the Midwest and South with the cross-country storm moving east.

A dangerous tornado outbreak which started on Friday evening continued into the first half of the weekend with nearly 2 dozen deaths across the nation's heartland and South.

Portions of West Virginia, Ohio and Pennsylvania were under a new tornado watch issued on Sunday by the National Weather Service, as the death toll from storms rose to at least 34 people in six states since Friday.