Official Discussion issued by the National Hurricane Center
IKE (AL092008) DATA RELEASED: 9/4/2008 3:00:00 PM UTC
Copy of official data HURRICANE IKE DISCUSSION NUMBER 14 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008 1100 AM EDT THU SEP 04 2008 IKE CONTINUES TO DISPLAY A WELL-DEFINED EYE WITH VERY COLD CLOUD TEMPERATURES IN THE EYEWALL. HOWEVER THE CLOUD PATTERN IS NOW ASYMMETRIC DUE TO SOME NORTHERLY SHEAR AFFECTING THE CYCLONE. OBJECTIVE AND SUBJECTIVE DVORAK CLASSIFICATIONS HAVE COME DOWN A LITTLE BIT SO THE INITIAL INTENSITY IS REDUCED TO 120 KT. GLOBAL MODELS UNANIMOUSLY INCREASE THE SHEAR OVER IKE AND KEEP STRONG NORTHEASTERLY WINDS NEAR THE CYCLONE FOR THE NEXT FEW DAYS. THIS PATTERN SHOULD INDUCE A STEADY WEAKENING. IN ADDITION...INNER- CORE EYEWALL CYCLES COULD OCCUR...WHICH COULD WEAKEN IKE AS WELL. IN THE LONGER-TERM...THE SHEAR IS FORECAST TO RELAX AND SOME STRENGTHENING COULD OCCUR. HOWEVER...DEPENDING ON THE EXACT TRACK OF IKE...THE HURRICANE COULD BE IMPACTED BY COOLER WATERS NEAR THE SOUTHEASTERN BAHAMAS THAT HAVE BEEN STIRRED UP BY HANNA. THE OFFICIAL FORECAST IS LOWER THAN THE PREVIOUS ONE BUT STILL SHOWS IKE AS A POWERFUL HURRICANE THROUGHOUT THE PERIOD. IKE CONTINUES TO MOVE WEST-NORTHWESTWARD...AT ABOUT 290/14...A LITTLE SLOWER THAN BEFORE. A BEND TOWARD THE WEST AND WEST- SOUTHWEST SEEMS PROBABLE AS A HIGH BUILDS IN TO THE NORTHWEST OF IKE. THE STRENGTH OF THE HIGH IS THE BIG QUESTION MARK FOR FIRST PART OF THIS FORECAST WITH THE MODELS BECOMING INCREASINGLY DIVERGENT. THE MODELS HAVE SPLIT INTO TWO GENERAL CAMPS THIS MORNING. THE UKMET/GFS/HWRF ALLOW THE CYCLONE TO GAIN A LITTLE MORE LATITUDE INITIALLY...THEN SHOW LESS OF A WEST-SOUTHWESTWARD MOTION OVER THE NEXT SEVERAL DAYS. HOWEVER ANOTHER GROUP OF MODELS... COMPRISED OF THE NOGAPS/ECMWF/GFDN/GFDL...SHOW A FASTER TURN TOWARD THE WEST AND WEST-SOUTHWEST AND SUGGEST MORE OF A THREAT TO THE BAHAMAS. WITH CREDIBLE MODELS IN EACH GROUP...IT IS PROBABLY BEST TO STAY FAIRLY CLOSE TO THE OVERALL MODEL CONSENSUS. THE OFFICIAL NHC FORECAST IS CLOSE TO THE PREVIOUS ONE AND IS NEAR A BIAS-CORRECTED GLOBAL MODEL CONSENSUS. BECAUSE OF THE UNCERTAINTIES IN 4- AND 5-DAY TRACK FORECASTS...IT IS STILL TOO EARLY TO SAY WHAT LAND AREAS ARE LIKELY TO BE IMPACTED BY THIS HURRICANE. HOWEVER INTERESTS IN THE TURKS AND CAICOS ISLANDS AND THE SOUTHEASTERN BAHAMAS SHOULD BE MONITORING THE PROGRESS OF IKE. FORECAST POSITIONS AND MAX WINDS INITIAL 04/1500Z 23.2N 57.0W 120 KT 12HR VT 05/0000Z 23.8N 58.9W 115 KT 24HR VT 05/1200Z 24.0N 61.3W 110 KT 36HR VT 06/0000Z 23.6N 63.8W 105 KT 48HR VT 06/1200Z 23.0N 66.7W 100 KT 72HR VT 07/1200Z 22.5N 71.0W 100 KT 96HR VT 08/1200Z 23.5N 74.5W 105 KT 120HR VT 09/1200Z 25.5N 77.5W 105 KT $$ FORECASTER BLAKE |