Storms are disturbances in the atmosphere (air surrounding Earth) that bring severe weather: heavy rain and snow, high winds, lightning and thunder, tornadoes, and hail. There are storms that are mild, such as rainstorms, which are beneficial, bringing needed rainfall for plants, animals, and waterways. Yet storms also have the potential to cause great harm. Hurricanes batter coastlines and islands with high winds, drenching rain, and waves. Thunderstorms and blizzards can cause floods and dangerous traveling conditions. During thunderstorms, lightning can ignite brush fires, and hail can destroy crops. Tornadoes can cut swaths of destruction across anything in its path.

Storms occur in unstable or changing areas of the atmosphere where warm, light air rises rapidly from the land surface.

A digital composite picture and animation from the movie The Perfect Storm shows a boat attempting to climb a mounting open sea wave driven by hurricane force winds...