Most of you are likely familiar with what the eye of a hurricane is: the center of the storm that’s cloud-free and calm. However, the eyewall is anything but.

The eyewall is the most intense and dangerous part of a hurricane. It’s a ring of towering thunderstorms that surrounds the eye. While the eye might be eerily peaceful, the eyewall is where the storm's strongest winds and heaviest rains are found. This is the part of the storm that can cause the most damage when it passes over land.

Inside the eyewall, wind speeds can reach well over 100 mph in major hurricanes. These winds spiral around the eye in a tight, violent circle. The eyewall also produces intense bursts of rainfall that can lead to flash flooding, especially when the storm moves slowly or stalls over an area.

Interestingly, the eyewall isn’t always a fixed structure. As a hurricane evolves, the eyewall can change shape, shrink, or even be replaced in what’s known as an eyewall replacement cycle. During this process, a new outer eyewall forms and takes over, often causing temporary weakening until the new eyewall is formed, and it also signals that the storm may grow even larger.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.