What is a hurricane?

What is a hurricane?


A hurricane is a tropical cyclone; a large rotating area of low pressure that spins in the tropics and has sustained winds of 74 mph or more. These spinning storms carry with them high winds, a devastating storm surge, torrential rains, and even have the capacity to form hurricane spawned tornadoes.

In the Atlantic Ocean and the Eastern Pacific, these large tropical cyclones are called hurricanes, in the Western Pacific, they’re called typhoons, and in the Indian Ocean and near Australia, they’re simply called tropical cyclones. They spin counter clockwise in the Northern hemisphere, and clockwise in the Southern hemisphere.

The La Niña weather phenomenon has been shown to have an effect on hurricanes. A weakening La Niña is likely to produce less hurricanes, while a strengthening La Niña could mean more hurricanes. La Niña, and its counterpart El Niño both have major effects on if and how a hurricane forms.


How A Hurricane Forms

Learning about hurricanes begins with understanding hurricane formation. In the Atlantic Ocean, hurricanes most often form from tropical waves off the coast of West Africa.

Tropical waves off of Africa

As these low pressure systems move over warm tropical waters, they build strength and move through different stages of development before forming into a fully fledged hurricanes. How a hurricane forms and if it ever forms depends on water temperature, wind sheer, and the pressence of land masses that disrupt development.

Our Hurricane Category Guide describes in depth the wind speeds, typical damage, and storm surges associated with Hurricane categories 1 through 5.