What process replaces a hurricane's inner eyewall with a larger outer eyewall?

What process replaces a hurricane’s inner eyewall with a larger outer eyewall? It is an eyewall replacement cycle.

An eyewall replacement cycle occurs when a hurricane’s outer rainbands organize into a new ring of thunderstorms outside the original eyewall. The new outer eyewall gradually moves inward and takes over the storm’s supply of moisture and angular momentum.

During the transition, the inner eyewall usually weakens and disappears. Because the eyewall contains a hurricane’s strongest winds, the storm often temporarily loses intensity while the replacement is occurring. Once the outer eyewall becomes established, the hurricane may re-intensify, sometimes with a larger eye and a broader wind field.

These cycles are most common in intense hurricanes, especially major hurricanes rated Category 3 through 5. They can produce sudden changes in wind speed and expand the area affected by damaging winds, even when the peak intensity falls.

The process was once considered a possible result of human cloud-seeding experiments. Observations later showed that concentric eyewalls occur naturally, helping demonstrate why Project Stormfury’s proposed weakening mechanism was not reliably artificial.