Eye Replacement Question

[Possum Trot]

I asked this question within an earlier thread and lost track of which thread it was, so I'll ask again. How long is a typical Eye Replacement Cycle, and what factors tend to effect the length of the cycle?

[ericinmia]

I asked this question within an earlier thread and lost track of which thread it was, so I'll ask again. How long is a typical Eye Replacement Cycle, and what factors tend to effect the length of the cycle?

Double eye walls, shear, water temps, friction with land, etc. effect it...

It will last between 6-20 hours... depending on the storm possibly quicker, or longer. There are countless more complexities in the reasoning for length of an ERC than there are in almost any other weather feature.
-Eric

Edit:
sorry, btw this cycle should be complete a few hours before landfall in Jamaica. Allowing the storm to possible regenerate into cat5.

[Possum Trot]

Thanks Ericinmia. I've noted you and others predicting that the cycle would complete before landfall and I guess I'm wondering how you make that determination. If there are countless complexities, perhaps it is more art than science.

God bless the people in Jamaica. Power 106 is streaming kickin' reggae. I can't think of a better way to pass the time in Jamaica waiting for Ivan.

[ericinmia]

You can determine the phase of the ERC and the length it most probably will take based on its current speed. Not the storms motion, but the speed of the ERC completion. By looking into the Vortex recon reports... you can see its progress bassed on temp differences, pressures, whether the eye is open or closed, whether it has dual eye walls, and a few other things. Then suplementally you can look on WV imagery and determine the health of the eye.

I hear ya.. sometimes just throw up your hands, and forgetaboutit... put on some music... and ride it out... reggae is meant for this...

God speed, and god bless them, and all that are impact by catastrophes of nature.
-Eric

[Possum Trot]

Okay, I kinda see where you're going. I'm just recently getting the hang of reading the vortex recon reports, and it seems as though there is a learning curve with practice involved in making any predictions about tropical storms. Now I know to look at the recon reports when you and others make ERC predictions and maybe I'll begin to recognize some patterns. Thanks again. I better get some sleep. Good night.

[banshee]

I asked an eyewall question earlier and guess the question got lost. Can someone please explain the ERW. When, why and how it happens.

[B-Bear]

Here's the short version:

Eyewall replacement cycles occur when a hurricane forms concentric eyewalls, meaning one eyewall inside another. As the storm strengthens and the wind speeds increase, the eyes begin to tighten and become smaller. The outside eyewall appears to constrict the inner eyewall. Eventually the inner eyewall will become constricted to the point where it can no longer perform its function properly, and it will begin to fall apart. The outside eyewall will then become the new inner eyewall, and the size of the eye will thus increase--albeit usually only temporarily. As the new eyewall begins to contract it allows the storm to strengthen. That's why eyewall replacement cycles are often a precursor to storm strengthening.

[HurricaneGirl]

What category does a hurricane have to be to go through an eyewall replacement ? Or do all hurricanes do it regardless of it's intensity?

[banshee]

Thank you b-bear. Next question....why do they form concentric eyewalls? Is it because there is so much spinning and pressure the clouds get heavier and move in towards the center?