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#47353 (Received by flhurricane at: 10:31 PM 20.Sep.2005) TCDAT2 TROPICAL STORM PHILIPPE DISCUSSION NUMBER 15 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT TUE SEP 20 2005 WESTERLY SHEAR...DUE TO AN UPPER-LEVEL LOW NEAR 23N 60W...CONTINUES TO INHIBIT RE-INTENSIFICATION OF PHILIPPE. THE CLOUD PATTERN REMAINS QUITE DISORGANIZED WITH LITTLE SEMBLANCE OF BANDING FEATURES...WHILE DEEP CONVECTION CONTINUES TO REDEVELOP AND SUBSEQUENTLY SHEAR AWAY FROM THE LOW-LEVEL CENTER. THE GFS PREDICTS THAT THE UPPER LOW WILL DEGENERATE INTO A NORTHEAST- SOUTHWEST SHEAR AXIS...AND THAT THE SHEAR OVER PHILIPPE WILL WEAKEN WITHIN 24 HOURS OR SO. THEREFORE PHILIPPE MAY HAVE AN OPPORTUNITY TO RESTRENGTHEN INTO A HURRICANE...AND THIS IS REFLECTED IN THE OFFICIAL FORECAST. HOWEVER IT SHOULD BE NOTED THAT THE GLOBAL MODELS HAVE BEEN KNOWN TO HAVE DIFFICULTY PREDICTING TROPICAL 200 MB FLOWS...AND THE SHEARING OVER THE STORM MAY NOT RELAX. IN ANY EVENT...AROUND 48 HOURS...THE UPPER-LEVEL WINDS ARE EXPECTED TO BEGIN TO BECOME SIGNIFICANTLY STRONGER...WHICH SHOULD INDUCE A FINAL WEAKENING TREND. BY 5 DAYS...GLOBAL GUIDANCE SHOWS PHILIPPE MERGING WITH A POWERFUL EXTRATROPICAL CYCLONE OVER THE NORTH ATLANTIC. IT IS DIFFICULT TO LOCATE THE CENTER OF THIS SHEARED TROPICAL CYCLONE USING INFRARED IMAGERY. MY BEST ESTIMATE OF INITIAL MOTION IS 340/5. REASONING FOR THE TRACK FORECAST REMAINS BASICALLY UNCHANGED. PHILIPPE SHOULD CONTINUE TO MOVE SLOWLY NORTH-NORTHWESTWARD TO NORTHWARD...THROUGH A WEAKNESS IN THE SUBTROPICAL RIDGE...UNTIL IT PASSES ABOUT 32N. AFTERWARD THE SYSTEM SHOULD RECURVE AND ACCELERATE INTO THE WESTERLIES. THE CURRENT OFFICIAL TRACK FORECAST IS MAINLY AN EXTENSION OF THE PREVIOUS ONE. FORECASTER PASCH FORECAST POSITIONS AND MAX WINDS INITIAL 21/0300Z 19.3N 57.6W 55 KT 12HR VT 21/1200Z 20.7N 57.8W 55 KT 24HR VT 22/0000Z 22.9N 58.1W 60 KT 36HR VT 22/1200Z 25.2N 58.9W 65 KT 48HR VT 23/0000Z 27.5N 59.5W 65 KT 72HR VT 24/0000Z 32.5N 59.0W 55 KT 96HR VT 25/0000Z 38.0N 52.0W 50 KT 120HR VT 26/0000Z...ABSORBED BY EXTRATROPICAL LOW |