Hurricanes are the most powerful storms on Earth. People call these storms by other names, such as "typhoons" or "cyclones," depending on where they occur. The scientific term for all these storms is tropical cyclone. Only tropical cyclones that form over the Atlantic Ocean, including the Gulf of Mexico, or eastern Pacific Ocean are called "hurricanes." Tropical cyclones that form over the western Pacific Ocean are called typhoons while cyclones that form over the Indian Ocean are just referred to as cyclones.

Whatever they are called, tropical cyclones all form the same way. What do hurricanes need to form? Use this animation to determine the conditions needed for a hurricane to form.

This activity might not be viewable on your mobile device.Interactive exercise. Assistance may be required.Create a Hurricane

From the animation, you learned that hurricanes form over the oceans near the equator and need low pressure, wind shear, and water temperatures over 27° C (80° F).


Video segment. Assistance may be required. But how does the hurricane actually form? Watch this video to learn more.

Source: Anatomy Of a Hurricane, ProfessorRitter, YouTube


Meteorologists have divided the development of a tropical cyclone into four stages: tropical disturbance, tropical depression, tropical storm, and tropical cyclone or hurricane.

Interactive exercise. Assistance may be required. Click on each image below.


Hurricanes get their energy from the condensation of water vapor and are fueled through contact with warm ocean water. Moisture is added to the warm air by evaporation from the ocean. As the warm air rises, the water vapor condenses, releasing large amounts of energy. The hurricane continues to grow as long as it's over its source of warm, moister air.


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