Official Discussion issued by the National Hurricane Center
IKE (AL092008) DATA RELEASED: 9/6/2008 9:00:00 PM UTC
Copy of official data HURRICANE IKE DISCUSSION NUMBER 23 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008 500 PM EDT SAT SEP 06 2008 AN AIR FORCE RECONNAISSANCE AIRCRAFT CURRENTLY INVESTIGATING IKE INDICATES THAT THE CYCLONE HAS AGAIN INTENSIFIED. THE PLANE REPORTED A PEAK SFMR WIND OF 118 KT AND FLIGHT-LEVEL WINDS OF 129 KT. ADDITIONALLY...CALCULATIONS FROM A DROPSONDE RELEASED IN THE NORTHEAST EYEWALL SUGGEST SURFACE WINDS OF AT LEAST 110 KT. BASED ON THESE DATA...THE INITIAL INTENSITY IS INCREASED TO 115 KT. WITH THE VERTICAL SHEAR OVER IKE NOW RELAXING AND THE WATERS ALONG THE FORECAST TRACK WARM...ADDITIONAL STRENGTHENING IS POSSIBLE UNTIL IKE REACHES CUBA IN ABOUT 36 HOURS. ONCE OVER LAND...WEAKENING IS ANTICIPATED UNTIL THE CYCLONE EMERGES BACK OVER WATER IN THE SOUTHEASTERN GULF OF MEXICO IN ABOUT 72 HOURS. HOWEVER...ONLY A SMALL DEVIATION NORTH OR SOUTH OF THE FORECAST TRACK WOULD KEEP THE CORE OF THE CYCLONE OVER WATER AND LESS WEAKENING COULD OCCUR. SOME RESTRENGTHENING IS FORECAST ONCE IKE DEPARTS CUBA SINCE ENVIRONMENTAL CONDITIONS APPEAR TO BE FAVORABLE FOR DEVELOPMENT. IKE CONTINUES TO BE STEERED BY A LARGE MIDDLE TO UPPER-LEVEL RIDGE OVER THE WESTERN ATLANTIC WITH AN INITIAL MOTION ESTIMATE OF OF 255/13. GLOBAL MODELS FORECAST THE RIDGE TO SHIFT EASTWARD DURING THE NEXT COUPLE OF DAYS ALLOWING IKE TO MAKE A TURN WESTWARD. IN 3 TO 4 DAYS...AS IKE MOVES INTO THE GULF OF MEXICO...A SHORTWAVE TROUGH MOVING OVER THE EASTERN UNITED STATES IS EXPECTED TO CREATE A WEAKNESS TO THE NORTH OF IKE RESULTING A TURN TOWARD THE WEST-NORTHWEST OR NORTHWEST WITH A DECREASE IN FORWARD SPEED. THIS SHORTWAVE TROUGH IS THE CRITICAL PLAYER IN IKE'S EVENTUAL TRACK AT THE EXTENDED RANGES. DYNAMICAL MODELS ARE STILL SPLIT INTO TWO CAMPS...WITH THE GFDL MODEL SHOWING IKE TURNING NORTHWARD INTO THE WEAKNESS...WHILE THE REST OF THE MODELS SHOW THE SHORTWAVE BYPASSING IKE TO THE NORTH AND KEEP THE CYCLONE MOVING WEST-NORTHWESTWARD. IT IS STILL MUCH TOO SOON TO COMMIT TO EITHER ONE OF THESE EXTENDED RANGE SOLUTIONS...AND ONLY A SLIGHT SOUTHWARD SHIFT IS MADE TO THE PREVIOUS OFFICIAL TRACK FORECAST. FORECAST POSITIONS AND MAX WINDS INITIAL 06/2100Z 21.4N 69.7W 115 KT 12HR VT 07/0600Z 21.2N 71.6W 120 KT 24HR VT 07/1800Z 21.1N 74.0W 125 KT 36HR VT 08/0600Z 21.2N 76.5W 120 KT...INLAND OVER CUBA 48HR VT 08/1800Z 21.7N 78.7W 95 KT...INLAND OVER CUBA 72HR VT 09/1800Z 23.0N 82.5W 80 KT...INLAND OVER CUBA 96HR VT 10/1800Z 25.0N 85.0W 90 KT 120HR VT 11/1800Z 26.5N 87.0W 100 KT $$ FORECASTER RHOME/BEVEN |