Tropical cyclones technically occur everywhere, although people call strong versions of these storms in certain areas hurricanes or typhoons. Hurricanes occur in the North Atlantic Ocean, Northeast Pacific Ocean and the South Pacific Ocean. Tropical cyclones occur specifically south of the equator, primarily in the Southwest region of the Indian Ocean. Other forms of tropical cyclones are tropical depressions and tropical storms.
A tropical cyclone is a storm system with a large low-pressure center. It is often accompanied by numerous thunderstorms and heavy winds and rains. In the northern hemisphere, the storms swirl counterclockwise. In the southern hemisphere, they swirl clockwise. Storms must have a wind speed of over 17 meters per second to be called a tropical cyclone, at which point they form a funnel-like body. Anything less is called a tropical depression. Cyclones are given names that refer to flowers, animals, birds, trees or foods.
A hurricane contains thunderstorms, rain and strong winds within a large circulating surface. Hurricanes have winds of 74 mph or faster. Hurricanes are categorized on a scale of one to five, with five being highest intensity. When the winds of a water storm reach 39 mph, the storms are given names, which alternate between male and female names.
Three conditions must be met for hurricanes to occur. The water must be warm, evaporation must leave a lot of steam on the surface, and the winds must be strong enough to cause the swirling motion. Most hurricanes occur in the aftermath of a previous storm, in which the waters and winds are already highly reactive. Eventually, the winds cause a swirling motion that pulls water into the air. After a while, the volume of water in the air increases and the hurricane forms.