Official Discussion issued by the National Hurricane Center

IKE (AL092008) DATA RELEASED: 9/8/2008 9:00:00 AM UTC

Copy of official data

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.


FORECAST POSITIONS AND MAX WINDS

INITIAL      08/0900Z 21.2N  77.3W    90 KT...INLAND
12HR VT     08/1800Z 21.6N  79.0W    75 KT...INLAND
24HR VT     09/0600Z 22.4N  81.2W    65 KT...INLAND
36HR VT     09/1800Z 23.1N  83.0W    60 KT...EMERGING INTO GULF
48HR VT     10/0600Z 23.9N  84.5W    75 KT
72HR VT     11/0600Z 25.5N  87.0W    90 KT
96HR VT     12/0600Z 27.0N  90.0W   100 KT
120HR VT     13/0600Z 28.5N  93.0W   100 KT

$$
FORECASTER FRANKLIN