Hurricanes are products of the interaction between tropical ocean and the atmosphere.
They are powered by heat energy from the sea, and are steered by the easterly trade winds and the temperate westerlies as well as by their own energy. Around its core, winds grow with great velocity, generating violent seas. Moving ashore, they sweep the ocean inward while spawning tornadoes and producing torrential rains and floods. Many of these remain over the ocean. However, about five hurricanes strike the United States coastline every 3 years.