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.

About 47 million people faced an enhanced to moderate severe storm threat from Madison, Wisconsin, to Birmingham, Alabama.

Violent tornadoes and high winds decimated homes, wiped out schools and toppled semitractor-trailers as a monster storm that killed at least 32 people ripped its way across the central and southern U.