A dynamic storm that prompted foreboding predictions of dangerous weekend weather spawned tornadoes, dust storms and wildfires that killed at least 39 people and destroyed hundreds of homes and businesses.

A severe storm on Monday swept through the U.S. Southeast and Mid-Atlantic, bringing thunderstorms, hail, damaging winds and the potential for tornadoes. Days earlier, the same ferocious weather system spawned violent twisters,

Thousands of power outages were reported Saturday as a deadly severe weather outbreak moved across the Midwest and South.

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.

In some extreme cases, thunderstorms can spawn a derecho, a long-lived windstorm with gusts over 100 mph, strong enough to cause widespread destruction. If a severe thunderstorm warning mentions damaging winds or a derecho, take cover immediately—just as you would for a tornado.