Collapsing cores and eyewall replacement

[wobblehead]

Ever wonder why people who have a cat2 or 3 hurricane pass over them swear it was a cat4 or 5? What they experienced may indeed have been stronger than the official classification. Take hurricane Ivan as an example. Today a local hurricane researcher showed me a dopplar radar image of Ivan at landfall. A cross sectional image looking east from Mobile. The coast on the left and GOM on the right. Upper right corner displayed a moisture mass in the upper levels. The next image displayed this same moisture mass down at the surface. As explained to me this was a huge mass of moisture that becomes so heavy it plummets downward hitting the strongest wind levels below it and pushes these winds down to the surface creating a huge and powerfull wind blast. For some reason this event is more common with exposed eyewall systems.
Also I learned that Katrina hit Ms with 2 eyewalls as proven in microwave imaging of the storm shortly before landfall. As the new eyewall forms outside the original eyewall the energy in the space now taken by the new eyewall must go somewhere so naturally it displaces outward (can't go back to lp center) thus increasing the overall size of the system ie Katrina.
You all may find this boring but I found it to be fascinating so I share it. Knowledge is good!

[ncupsscweather]

Yes that is very fascinating thanks for shareing.

[Tampa Bay Hurricane]

Very Fascinating!