In the Atlantic Ocean, they are called hurricanes. In the Pacific Ocean, they are usually referred to as typhoons. Tropical storms become hurricanes once their winds exceed 74 mph. Hurricanes produce strong and sustained winds, torrential rain, and storm surges which can inundated coasts. The results can include coastal flooding, coastal erosion, destruction of property, and even loss of life.
Tropical cyclones come in a variety of strengths and sizes, and are classified by peak wind speed.
A tropical depression is an organized cluster of thunderstorms with sustained winds below 38 mph. A tropical storm is more organized, with sustained winds in the 39 to 73 mph range. A hurricane has winds of 74 mph and up. Hurricanes can, in increasing order of severity, from Category 1 through Category 5. Check out an animated description of the Saffir-Simpson Scale .