Powerful storms such as thunderstorms, hurricanes, and tornadoes are generated when warm, light air rises quickly into higher, colder levels in an unstable updraft that can reach over 100 miles per hour. Each type of storm forms under specific conditions; hurricanes occur over moisture-rich oceans and coastlines, for example. They draw their energy from warm ocean waters. Understanding the conditions that give rise to powerful storms is the key to preparing for their devastating effects.