Official Discussion issued by the National Hurricane Center
IKE (AL092008) DATA RELEASED: 9/9/2008 3:00:00 PM UTC
Copy of official data HURRICANE IKE DISCUSSION NUMBER 34 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008 1100 AM EDT TUE SEP 09 2008 RADAR AND RECONNAISSANCE OBSERVATIONS SHOW THAT IKE IS MAINTAINING A SMALL AND WELL-DEFINED EYEWALL...AND THE SATELLITE PRESENTION IS THAT OF A STRONGER STORM THAN THE RECONNAISSANCE WIND DATA SUPPORT. THE CENTRAL PRESSURE WAS 965 MB ON THE LAST PASS...BUT THE PEAK FLIGHT LEVEL WINDS WERE NO HIGHER THAN 66 KT. SFMR DATA SEEM TO SUPPORT A 65 KT INTENSITY...BUT SINCE THERE WAS LIMITED SAMPLING IN THE NORTHEAST QUADRANT THE ADVISORY ESTIMATE WILL REMAIN 70 KT. THE INITIAL MOTION IS 290/11. IKE IS EXPECTED TO MOVE GENERALLY WEST-NORTHWESTWARD FOR THE NEXT DAY OR TWO IN RESPONSE TO A WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE NORTHEASTERN GULF OF MEXICO. AFTER THAT...RIDGING OVER THE SOUTHEASTERN STATES IS EXPECTED TO BEND THE TRACK SLIGHTLY TO THE LEFT IN THE CENTRAL GULF...AND THE GUIDANCE IS IN PRETTY GOOD AGREEMENT THROUGH 72 HOURS. THERE IS CONSIDERABLE UNCERTAINTY NEAR THE END OF THE FORECAST PERIOD...WITH THE ECMWF AND UKMET MODELS SHOWING A SHORT-WAVE TROUGH COMING OUT OF THE ROCKIES THAT INDUCES A RIGHT TURN ON DAY 4. THE GFS AND NOGAPS HAVE A DIFFERENT PATTERN...WITH MORE RIDGING EXTENDING WESTWARD TO THE NORTH OF IKE THAT KEEPS THE HURRICANE MOVING BASICALLY WESTWARD. THE ECMWF HAS DONE VERY WELL WITH IKE THUS FAR...AND HAS RELATIVELY HIGH SKILL IN FORECASTING THE LARGE SCALE PATTERNS AT THE LONGER RANGES. OUT OF RESPECT FOR THIS MODEL THE OFFICIAL FORECAST IS SHIFTED SLIGHTLY SLOWER AND TO THE RIGHT OF THE PREVIOUS FORECAST...AND IS PRETTY CLOSE TO THE DYNAMICAL MODEL CONSENSUS. BEGINNING TOMORROW AT 12Z THE NOAA G-IV JET AIRCRAFT WILL BE SAMPLING THE ENVIRONMENT OF IKE TO ASSIST IN THE DETERMINATION OF WATCHES AND WARNINGS. WHEN IKE IS IN THE SOUTHEASTERN GULF OF MEXICO IT WILL BE IN A VERY DIFLUENT AND FAVORABLE ENVIRONMENT FOR RESTRENGTHENING...AND IKE IS EXPECTED TO REGAIN MAJOR HURRICANE STATUS. THE PATTERN LOOKS A LITTLE LESS CONDUCIVE IN THE WESTERN GULF...WITH SOME NORTHEASTERLY SHEAR...SO THE OFFICIAL FORECAST SHOWS NO FURTHER STRENGTHENING THERE. THE OFFICIAL FORECAST IS A BLEND OF THE STATISTICAL GUIDANCE...WHICH IS BASICALLY CATEGORY 2...AND THE DYNAMICAL GFDL/HWRF WHICH SHOW CAT 3/4 STRENGTH IN THE WESTERN GULF. FORECAST POSITIONS AND MAX WINDS INITIAL 09/1500Z 22.6N 83.0W 70 KT 12HR VT 10/0000Z 23.2N 84.2W 70 KT 24HR VT 10/1200Z 24.0N 85.8W 85 KT 36HR VT 11/0000Z 24.7N 87.4W 95 KT 48HR VT 11/1200Z 25.2N 89.2W 100 KT 72HR VT 12/1200Z 26.0N 93.5W 100 KT 96HR VT 13/1200Z 27.5N 97.0W 100 KT 120HR VT 14/1200Z 29.0N 99.5W 40 KT...INLAND $$ FORECASTER FRANKLIN |