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Infographic: An inside look at the birth and power of hurricanes

Hurricanes, swirling ocean storms that can be seen from space, are both captivating and terrifying to behold. These weather systems, as large as 1,000 miles in diameter, present three threats: winds destructive enough to tear apart buildings, storm surges that can swamp coastal areas, and torrential rains that can cause devastating inland flooding. If you’re curious how hurricanes work, these graphics give you an inside look at their birth and devastating power.

It starts over warm water

Hurricanes are born in the tropics, above warm water. Clusters of thunderstorms can develop over the ocean when water temperatures exceed 80 degrees Fahrenheit. If conditions are right, the clusters swirl into a storm known as a tropical wave or tropical depression.

A tropical depression becomes a named tropical storm once its wind speed reaches 39 miles per hour. When its wind speed hits 74 mph, the storm officially becomes a hurricane.

To truly understand how hurricanes forms, you need to look inside these massive storms.

Internal workings of a hurricane

A hurricane has three main parts:

The eye is the calm, low-pressure center of the storm, usually about 30 miles in diameter. Winds are low to nonexistent.

The eyewall ­­surrounds the eye and contains the strongest winds and rain. Winds can reach 200 mph.

Rain bands are surrounding clouds that swirl outward and increase the hurricane’s size.

The mechanics of wind

Inside the hurricane, warm, humid air circles inward around the eye, speeding up as it approaches the center. Air also rises outside the eyewall, under the bands of thunderstorms around the hurricane.

These thunderstorm bands are typically 3 to 30 miles wide and 50 to 300 miles long.

The destructive winds of a hurricane are created by swaths of air spinning both counter-clockwise and up.

Once the spinning air reaches the top of the eyewall, it sinks 20 to 40 feet a minute into the hurricane’s eye, warming it and suppressing clouds and wind.

While the 74- to 175-mph winds created by hurricanes are feared, hurricane storm surges can be even more deadly.

In open ocean, hurricane winds push water toward the center of the storm. The water spirals downward into the ocean, creating underwater currents.

As the hurricane approaches the shallow water near land, the ocean floor blocks the water from flowing away. The resulting storm surge sends high waves of water roaring onto land.

Just how powerful is the wind?

Here is a breakdown using the Saffir-Simpson hurricane wind scale:

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SOURCE Live Science; NASA; University of Illinois; University Corporation for Atmospheric Research

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This article originally appeared on USA TODAY: How do hurricanes form? An inside look – USA TODAY