A cross-country storm will explode in strength as it moves over the central United States Friday, delivering extreme weather to millions through the weekend, including the chance of multiple strong tornadoes.

A multi-day outbreak of severe thunderstorms will begin today and last through the weekend in the Midwest, South and East. Strong, long-tracked tornadoes, widespread damaging winds, large hail and flash flooding are all threats this dangerous bout of severe weather could produce.

Weather forecasters warn about a major multiple-day outbreak of severe weather that includes multiple strong tornadoes from the Mississippi Valley to the Gulf Coast, Great Lakes and Atlantic coast through the weekend.