Matthew5 wrote:Southernwx, Ivan did not look like your normal cat4 hurricane...It had a open western quad of its eyewall. It also was unbounced with most of its strong winds on its eastern-northeastern quad. If you look at Jeanne it is a closed system with a much more defined eyewall...So Tell me if I'm mistaking?
Matthew, every hurricane is different...something I've learned from three decades of research. You can't judge a hurricane's intensity by a radar appearance or even recon data....
Why do I estimate Ivan's wind speeds at 115 kt, gusting to 140-150 kt? Visual wind damage....using the Fujita scale, the same way I've rated tornadoes for years. I've seen several hi-rise structures along the beachfront with large sections of the exterior walls missing....eerily similar to the Burger King headquarters building near Perrine, Florida after Andrew passed through. The damage to these beachfront structures was caused by wind....it was above the third floor..above the storm surge level. There was also several complete building failures in Pensacola...I saw them on Atlanta's WSB-TV news; one family who survived their home collapsing in stated the wind was "just like a bomb went off"...then the house began coming apart. It was a frame home with F3 damage....160 mph in my estimation. This wasn't a tornado...not in the inner core at landfall...it was an explosive burst of wind from the hurricane.
I just checked out the AOML experimental chart you posted. That 95 kt surface wind report was based on 0400z SMFR data....the NOAA research aircraft left the area over two hours before landfall occurred. I noted the eyewall convection in Ivan intensified significantly during those 2 1/2 hours....just as the hurricane was coming ashore (and in the area just east of Gulf Shores...eastward to Perdido Key...where max winds occurred, based on visual damage photos).
Just look at the rapid increase in Jeanne's surface wind field at time of landfall last night....one surface estimate near the shoreline north of Fort Pierce of 112 kts at time of landfall....almost 130 mph. That is IMO what happened with Ivan....but there was no NOAA P-3 in the hurricane with SMFR capability. Look at how Jeanne changed...the 11 p.m. advisory stated Jeanne might NOT even be a cat-3 based on flight data from 8-10 p.m.....but within an hour, the NOAA aircraft was measuring 113 kt at flight level and 100-112 kt at the surface.
I've rated and surveyed hurricane wind damage since 1979....my first two up-close encounters with hurricanes David and Frederic. If I didn't feel confident that Ivan was stronger than Opal and Frederic at landfall....I wouldn't post it.
FYI - you mentioned the fact part of Ivan's eyewall eroded away prior to landfall. Two observations....1) so did Opal's, except it was being sheared, over 78° sst's, and even more disorganized...yet 144 mph gusts were measured at Hurlburt Field (incidentally the same anemometer which was destroyed by Ivan)...and 2) at time of landfall, Ivan's eyewall looked the most intense it had in several hours....it was definitely better organized at 0700z than at 0400z.
