Margie
(Senior Storm Chaser)
Thu Oct 20 2005 01:13 PM
Re: Movement

Good morning all.

I am still totally blown away by Wilma. She has managed to keep to an amazingly low pressure and amazingly good organziation and symmetry, during an ERC, and is completing it much more rapidly than I expected.

From one extreme to the other LOL...we had the 2nm-wide eye, so why not now try a 40nm-wide one?

At buoy 42056 waves are now up to 25 ft and will get higher as Wilma passes by today.

Even though she is not under the warmest water (to the east of her), she will be skirting it if she follows the forecast track, so I believe she'll still be able to spin up rapidly today and easily get back to a Cat 5 before the Yucatan starts impacting her, especially if she starts the northward turn early today.

This is because even though she is technically weakening for the moment in terms of pressure and windspeed, in a sense she is not weakening, because her structure is improving with every sat image, and convection is regularly expanding and building a symmetric strong hurricane-force windfield. This time she is building a more typical windfield where strong hurricane-force winds will extend outward for most of the main circulation. The most optimistic strengthening indicates she's going to become a very strong donut; however there are unanticipated things that can throw a wrench in reorganization. Once the eyewall clears out, given her track record with pressure, I would not even be surprised to see a very low pressure again towards evening.

But this final leg of the trek through the NW Caribbean will be her last hurrah with impressive pressures and windspeeds. If she follows the forecast models and goes into the GOM towards FL, she'll brush the loop current and may be able to maintain Cat 4 status while north of western Cuba, but that will probably be it. But, since every hurricane has its own characteristics, like a personality, consider that Wilma has been very tenacious with hanging onto low pressures (again, I'm still in amazement), so we can expect low pressures (with windspeeds continuing to lag behind the low pressure) and a very solid core, to remain even during the trip over the GOM. She may even be able to maintain higher winds than expected by once again reducing the size of the eyewall while over the GOM. Whatever it is about the unique characteristics of each hurricane, I have come to believe that if we see a specific behavior with one particular hurricane then there is more of a likelyhood of that behavior being repeated before landfall.

One final note -- since we are not not seeing the oscillating eyewall I tend to agree with the previously-posted idea that the very strong inner eyewall was rotating around the outer wind maximum (that has become the 40-mile-wide eyewall today), and the "inertia" was resulting in the looping movement. Because there was such a dramatic difference between the strength of the very small core compared with the remaining windfield, which was for the most part 80kts and lower, the movement was amplified.



Note: This is NOT an official page. It is run by weather hobbyists and should not be used as a replacement for official sources. 
CFHC's main servers are currently located at Hostdime.com in Orlando, FL.
Image Server Network thanks to Mike Potts and Amazon Web Services. If you have static file hosting space that allows dns aliasing contact us to help out! Some Maps Provided by:
Great thanks to all who donated and everyone who uses the site as well. Site designed for 800x600+ resolution
When in doubt, take the word of the National Hurricane Center