HURRICANE IKE DISCUSSION NUMBER 29 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008 500 AM EDT MON SEP 08 2008

CUBAN RADAR OBSERVATIONS INDICATE THAT THE CENTER OF IKE CONTINUES MOVING WESTWARD OVER CENTRAL CUBA. THE EYE IS STILL VISIBLE BUT THE EYEWALL IS NOW ENTIRELY OVER LAND AND ITS STRUCTURE HAS DEGRADED OVER THE PAST FEW HOURS. THE INITIAL INTENSITY IS LOWERED TO 90 KT. THE OFFICIAL FORECAST AGAIN SHOWS LESS WEAKENING OVER LAND THAN INDICATED BY THE DECAY SHIPS MODEL...IN THE EVENT THAT THE CENTER EMERGES OVER WATER SOONER THAN FORECAST. IF IKE FOLLOWS THE FORECAST TRACK IT WILL BE OVER LAND FOR ABOUT 36 HOURS...AND WOULD ALMOST SURELY BE WEAKER IN THE SOUTHEASTERN GULF THAN SHOWN HERE. NEVERTHELESS...THE ENVIRONMENT IN THE GULF IS EXPECTED TO BE VERY CONDUCIVE TO RESTRENGTHENING WITH A VERY DIFLUENT LIGHT SHEAR UPPER WIND PATTERN AND WARM WATERS BELOW. THE MAJOR UNKNOWN IS HOW DISRUPTED IKE WILL BE WHEN IT EMERGES.

THERE HAS BEEN NO SIGNIFICANT CHANGE TO THE FORECAST TRACK. IKE'S TRAJECTORY IS EXPECTED TO BEND GRADUALLY TO THE RIGHT AS THE STORM NEARS A WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE NEXT COUPLE OF DAYS...AND THE GUIDANCE MODELS ARE TIGHTLY CLUSTERED THROUGH 72 HOURS. AFTER THAT...THE GFS IS AN OUTLIER IN CALLING FOR A SHARP SHORT WAVE TROUGH TO MOVE THROUGH THE PLAINS STATES ON DAYS 4-5. THE GFDL AND HWRF...WHICH USE THE GFS FOR BOUNDARY CONDITIONS...MAY BE PICKING UP ON THAT AND SHOW A BEND TO THE RIGHT AT THE END OF THE FORECAST PERIOD. THE OTHER GLOBAL MODELS...SUCH AS THE ECMWF...SHOW MUCH MORE RIDGING OVER THE EASTERN UNITED STATES AT THOSE RANGES AND HAVE A MORE WESTWARD TRACK. EVEN THOUGH THE GFDL HAS PERFORMED VERY WELL WITH IKE SO FAR...I'VE CHOSEN NOT TO ADJUST THE TRACK EASTWARD GIVEN THAT THE LARGE-SCALE FIELDS IN THE GFS HAVE NO SUPPORT FROM THE OTHER MODELS. IT IS STILL TOO SOON TO KNOW WHAT PORTION OF THE GULF COAST WILL ULTIMATELY BE AFFECTED BY IKE.