|
Show Selection: |
| #8802 (Received by flhurricane at: 11:19 AM 16.Sep.2004) TCDAT1 HURRICANE JEANNE DISCUSSION NUMBER 12 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 AM EDT THU SEP 16 2004 AIRCRAFT AND DROPSONDE DATA THIS MORNING INDICATED THAT JEANNE REACHED HURRICANE STRENGTH NEAR THE EASTERN TIP OF HISPANIOLA. PEAK FLIGHT-LEVEL WINDS OF 88 KT...AND MULTIPLE DROPSONDE SURFACE ESTIMATES BETWEEN 63 AND 69 KT SUPPORT THE 70 KT INITIAL INTENSITY ESTIMATE. OVER THE PAST 12 HOURS JEANNE HAS BEEN MOVING 275/6. JEANNE IS SOUTH OF A MID-LEVEL RIDGE THAT SHOULD PRODUCE A GENERALLY WEST-NORTHWESTWARD MOTION OVER THE NEXT COUPLE OF DAYS...AND MODEL GUIDANCE IS VERY TIGHTLY CLUSTERED OVER THIS INTERVAL. AFTER THAT THERE IS CONSIDERABLE UNCERTAINTY DEPENDING ON THE EVOLUTION OF THE MID-LEVEL REMNANTS OF IVAN...WHICH COULD BE ANWHERE FROM THE TENNESSEE VALLEY TO CAPE HATTERAS IN THREE DAYS. THE MORE EASTERN SOLUTIONS RESULT IN A MORE NORTHERLY TRACK OF JEANNE THROUGH 5 DAYS...AS INDICATED BY THE GFS AND UKMET. MORE WESTWARD TRACKS...TOWARD FLORIDA...ARE INDICATED BY THE GFDL...ECMWF...AND FSU SUPERENSEMBLE. STEERING CURRENTS ARE EXPECTED TO BECOME WEAK IN ABOUT 48 HOURS AND IT IS NOT YET POSSIBLE TO CONFIDENTLY CHOOSE BETWEEN THE SCENARIOS OUTLINED ABOVE. THE OFFICIAL FORECAST LIES A LITTLE TO THE LEFT OF THE MODEL CONSENSUS...AND REPRESENTS A COMPROMISE BETWEEN THE EXTREMES OF THE GFS AND GFDL GUIDANCE. IT IS QUITE CURIOUS THAT THE SUPERENSEMBLE 5-DAY POINT LIES TO THE LEFT OF ALL OF ITS COMPONENTS...BUT THIS CAN HAPPEN GIVEN THE WAY THAT BIAS-CORRECTING MODEL IS CONSTRUCTED. JEANNE SHOULD WEAKEN BELOW HURRICANE STRENGTH OVER HISPANIOLA...BUT EVENTUALLY SHOULD COME UNDER LIGHT ANTICYCLONIC FLOW ASSOCIATED WITH THE REMNANTS OF IVAN. THIS...AND THE WARM WATERS OF THE BAHAMAS...SHOULD ALLOW RESTRENGTHENING. THE OFFICIAL FORECAST IS CLOSE TO THE GFDL AND SHIPS GUIDANCE. FORECASTER FRANKLIN FORECAST POSITIONS AND MAX WINDS INITIAL 16/1500Z 18.8N 68.7W 70 KT 12HR VT 17/0000Z 19.3N 70.0W 60 KT 24HR VT 17/1200Z 20.2N 71.7W 55 KT 36HR VT 18/0000Z 21.1N 73.4W 65 KT 48HR VT 18/1200Z 22.0N 75.0W 70 KT 72HR VT 19/1200Z 23.5N 76.5W 85 KT 96HR VT 20/1200Z 26.5N 78.0W 85 KT 120HR VT 21/1200Z 30.0N 79.5W 85 KT |
