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 moveing east.

Tornado activity has picked up in March, which is traditionally the start of tornado season, but the areas of activity have expanded in recent years.

A severe weather system spawned intense, long-duration tornadoes that struck parts of Arkansas, Mississippi and Missouri, leaving some communities in tatters.

A powerful storm system roared across the Midwest and South Friday night, unleashing a series of tornadoes that carved paths of destruction and left at least three dead in Missouri.

The threat of tornadoes is moving east into the Mississippi Valley and Deep South a day after a massive storm system moving across the country unleashed winds that damaged buildings, whipped up dust storms that caused deadly crashes and fanned