Looking at the morning visible satellite image from NRL Monterey CAT 4 Hurricane Ivan is undergoing another weakening cycle due to eyewall replacement as the north eyewall grazes Grand Cayman Island. I also notice a blowup of convection in his west eyewall much like CAT 4 Charley.

Looking at a long satellite image loop Ivan continues to slow his forward speed and is moving at more like 280 deg. then the 290 deg. (WNW) that the NHC is describing. If this current track holds then Ivan could clip the Yucatan Peninsula and become a threat to the mid Gulf Coast of the U.S. But, the blow up of convection in the west eyewall could be a sign that a more NW turn will begin soon. I can't put forth a big argument with the current NHC forecast track. BUT looking at the latest water vapor satellite image I see a slight weakening of the large Bermuda high pressure ridge and a strengthening and southward digging of the 500 mb shortwave in the vicinity of SE Texas/SW Louisiana. I think this trend will continue, with forecast models and the NHC official track coming back towards the east with time.

I think we will see Ivan return to CAT 5 status later today with a passage across the western end of Cuba west of the Isle Of Youth and then emerge into the Gulf Of Mexico around 84-85 deg. west longitude as a CAT 4 sometime on Tuesday September 14, 2004. Ivan will then encounter SW-W wind shear and weaken to a CAT 3-2 cyclone with a NNE-NE track landfall around Apalachicola. There is still a good "chance" for a further east landfall in the vicinity of Cedar Key with some damaging storm surge in the shallow estuary of Tampa Bay and northward along the Nature Coast.

I continue to monitor the NHC amateur radio weather net on 14325.0 kc. I'm hearing very few amateur radio operators on the air from Jamaica and no one from the Cayman Islands, a bad sign to me.

Thomas F. Giella
Retired Space & Atmospheric Weather Forecaster
Plant City, FL