000 WTNT42 KNHC 270246 TCDAT2 TROPICAL STORM PHILIPPE DISCUSSION NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011 1100 PM AST MON SEP 26 2011 AN ASCAT PASS CAUGHT PHILIPPE AT 2304 UTC...AND THE HIGHEST WINDS SHOWN IN THE SWATH WERE 40 KT WITHIN THE DEEP CONVECTION LOCATED TO THE SOUTHEAST OF THE LOW-LEVEL CENTER. THIS DATA SUGGESTS THAT THE INITIAL INTENSITY IS 45 KT...WHICH IS SUPPORTED BY SATELLITE INTENSITY ESTIMATES OF 45 KT FROM TAFB AND SAB. THIS IS THE FIRST REAL GROUND-TRUTH DATA WE HAVE RECEIVED OVER PHILIPPE IN A COUPLE OF DAYS...AND THE LOWERING OF THE INTENSITY SHOULD BE SEEN MORE AS AN ADJUSTMENT RATHER THAN A WEAKENING OF THE STORM. NONETHELESS... PHILIPPE IS EXPECTED TO MOVE INTO AN ENVIRONMENT OF INCREASING SOUTHWESTERLY SHEAR OVER THE NEXT DAY OR SO...AND THAT SHOULD LIMIT STRENGTHENING...IF NOT INDUCE SOME WEAKENING. THE SHEAR COULD DIMINISH BY DAY 3 AS THE CYCLONE MOVES INTO AN UPPER-LEVEL COL...AND THAT COULD BE JUST ENOUGH TO KEEP PHILIPPE FROM DEGENERATING INTO A REMNANT LOW. THE NHC INTENSITY FORECAST HAS BEEN LOWERED PRIMARILY DUE TO THE ADJUSTED INITIAL INTENSITY AND IS CLOSE TO THE INTENSITY CONSENSUS ICON THROUGH 48 HOURS AND THE SHIPS AND LGEM ON DAYS 3 THROUGH 5. THE INITIAL MOTION IS 315 DEGREES AT 7 KT. PHILIPPE IS FORECAST TO ACQUIRE A LITTLE MORE WESTWARD COMPONENT TO ITS MOTION OVER THE NEXT DAY OR TWO WHEN A LONGWAVE TROUGH TO THE NORTHWEST OF THE CYCLONE LIFTS NORTH AND A MID-LEVEL ANTICYCLONE BUILDS NORTH OF THE CAPE VERDE ISLANDS. THERE CONTINUES TO BE DIVERGENCE IN THE TRACK GUIDANCE AFTER 48 HOURS WITH SOME MODELS INDICATING A TURN TOWARD THE NORTH AND NORTHEAST WHILE ANOTHER SET...FIRST SHOWN BY THE ECMWF...MAINTAINS A NORTHWESTWARD MOTION. SINCE PHILIPPE IS FORECAST TO SLOWLY WEAKEN...IN THE OFFICIAL FORECAST ANYWAYS...IT SHOULD BECOME BLOCKED BY HIGH PRESSURE TO ITS NORTH AND WOULD MOST LIKELY FOLLOW THE WESTERN CLUSTER OF MODELS. THE OFFICIAL FORECAST IS THEREFORE A LITTLE WEST OF THE PREVIOUS FORECAST AND THE TVCA CONSENSUS...AND EVEN SHOWS A SLIGHT WESTWARD BEND AT DAY 5. FORECAST POSITIONS AND MAX WINDS INIT 27/0300Z 15.9N 34.8W 45 KT 50 MPH 12H 27/1200Z 16.5N 35.5W 45 KT 50 MPH 24H 28/0000Z 17.4N 36.6W 45 KT 50 MPH 36H 28/1200Z 18.3N 38.1W 40 KT 45 MPH 48H 29/0000Z 19.5N 39.4W 40 KT 45 MPH 72H 30/0000Z 22.0N 41.0W 35 KT 40 MPH 96H 01/0000Z 24.0N 41.5W 35 KT 40 MPH 120H 02/0000Z 25.0N 42.0W 35 KT 40 MPH $$ FORECASTER BERG