000 WTNT42 KNHC 022034 TCDAT2 TROPICAL STORM PHILIPPE DISCUSSION NUMBER 35 NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011 500 PM AST SUN OCT 02 2011 A NEW ROUND OF DEEP CONVECTION HAS REDEVELOPED OVER THE PAST SEVERAL HOURS...AND IS PARTIALLY COVERING THE LOW-LEVEL CENTER OF PHILIPPE. DVORAK CURRENT-INTENSITY ESTIMATES REMAIN AT 45 KT FROM TAFB AND SAB...AND THE UW-CIMSS ADT HAS RECENTLY INCREASED TO 45 KT DUE TO THE NEW CONVECTION. THEREFORE...THE WIND SPEED IS MAINTAINED AT 45 KT FOR THIS ADVISORY. WATER VAPOR IMAGERY AND CLOUD-TRACKED SATELLITE WINDS INDICATE THAT A 60-KT UPPER-LEVEL JET STREAK IS CURRENTLY POINTED DUE SOUTH INTO PHILIPPE...SO THE CYCLONE IS WITHIN AN ENVIRONMENT OF BELLIGERENT NORTHERLY SHEAR AND UPPER-LEVEL SPEED CONVERGENCE. THESE NEGATIVE FACTORS ARE EXPECTED TO CAUSE SOME WEAKENING AT LEAST FOR THE NEXT 48 HOURS. THE SHEAR COULD RELAX AND FOSTER SOME RE-STRENGTHENING BY DAY 3 WHEN PHILIPPE REACHES A NARROW UPPER-LEVEL RIDGE. HOWEVER...SOUTHWESTERLY VERTICAL SHEAR IS EXPECTED TO INCREASE IN EARNEST ON DAYS 4 AND 5...AND THIS WOULD BE A MUCH MORE UNFAVORABLE ENVIRONMENT THAN THE ONE PHILIPPE IS CURRENTLY EXPERIENCING. THE OFFICIAL FORECAST IS CLOSE TO THE INTENSITY CONSENSUS FOR MOST OF THE FORECAST PERIOD AND CONTINUES TO SHY AWAY FROM THE HURRICANE- PRODUCING GFDL AND FSU SUPERENSEMBLE. ON THE OTHER END OF THE SPECTRUM...THE ECMWF MODEL CONTINUES TO DISSIPATE PHILIPPE IN ABOUT 3 DAYS. PHILIPPE IS AVERAGING A MOTION OF 285 DEGREES AT 10 KT...BUT A SHORTER-TERM MOTION SUGGESTS THAT THE CYCLONE MAY HAVE TURNED TOWARD THE WEST AS FORECAST. THERE HAS BEEN A SOMEWHAT SIGNIFICANT SOUTHWESTWARD SHIFT IN THE TRACK GUIDANCE FOR THIS CYCLE. ALTHOUGH THE GFS HAS CONSISTENTLY SHOWN A MORE SOUTHERN TRACK WITH A WIDER AND SHARPER RE-CURVATURE COMPARED TO THE OTHER MODELS...THAT TREND IS EVEN MORE PRONOUNCED IN THE 12Z CYCLE. IN ADDITION...THE GFDL AND HWRF MODELS HAVE JOINED THE GFS IN THAT SOLUTION...AND EVEN THE ECMWF NOW SHOWS A SHARPER TURN. THE OFFICIAL TRACK FORECAST HAS BEEN SHIFTED A LITTLE SOUTH AND WEST OF THE PREVIOUS FORECAST FOR MUCH OF THE PERIOD AND IS VERY CLOSE TO THE MODEL CONSENSUS...EVEN SHOWING A BRIEF WEST-SOUTHWESTWARD MOTION IN ABOUT 24 HOURS. FORECAST POSITIONS AND MAX WINDS INIT 02/2100Z 26.3N 52.9W 45 KT 50 MPH 12H 03/0600Z 26.2N 54.5W 40 KT 45 MPH 24H 03/1800Z 25.7N 56.8W 35 KT 40 MPH 36H 04/0600Z 25.4N 59.1W 35 KT 40 MPH 48H 04/1800Z 25.5N 60.9W 35 KT 40 MPH 72H 05/1800Z 27.0N 62.0W 40 KT 45 MPH 96H 06/1800Z 29.0N 60.5W 45 KT 50 MPH 120H 07/1800Z 31.0N 57.0W 45 KT 50 MPH $$ FORECASTER BERG