000 WTNT44 KNHC 142033 TCDAT4 TROPICAL STORM NADINE DISCUSSION NUMBER 14 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142012 500 PM AST FRI SEP 14 2012 A 1624 UTC TRMM PASS SUGGESTS THAT THE CORE CONVECTION MAY BE IMPROVING IN ORGANIZATION...BUT THE MID-LEVEL CENTER IS DISPLACED ABOUT HALF A DEGREE NORTH OF THE LOW-LEVEL CENTER DUE TO VERTICAL SHEAR. DVORAK ESTIMATES REMAIN 65 KT FROM TAFB AND 55 KT FROM SAB...AND THE MOST RECENT UW-CIMSS ADT ESTIMATE HAS ACTUALLY FALLEN TO 55 KT. THE SATELLITE SIGNATURE SEEMS LARGELY UNCHANGED FROM THIS MORNING AND DOES NOT LEAD ME TO BELIEVE THAT NADINE HAS WEAKENED...SO THE INITIAL INTENSITY IS KEPT AT 60 KT. THE VERTICAL SHEAR IS NOT EXPECTED TO WEAKEN DURING THE FORECAST PERIOD. HOWEVER...THE SHEAR DIRECTION IS FORECAST TO CHANGE FROM SOUTHWESTERLY TO WESTERLY IN A DAY OR TWO...AND THE SHIPS GUIDANCE SHOWS THE NEGATIVE CONTRIBUTIONS OF STRONG SHEAR BEING CANCELED OUT BY THE POSITIVE CONTRIBUTIONS OF A MORE FAVORABLE SHEAR DIRECTION. AS A RESULT...THE STATISTICAL GUIDANCE SHOWS LITTLE CHANGE IN INTENSITY OVERALL...BUT DOES STILL PRESENT THE POSSIBILITY OF NADINE BECOMING A HURRICANE DURING THE NEXT FEW DAYS. THE HWRF SHOWS NADINE STRENGTHENING SIGNIFICANTLY IN A COUPLE OF DAYS...BUT THIS SCENARIO APPEARS LESS LIKELY SINCE THE CYCLONE WILL BE APPROACHING COLDER WATER. THE UPDATED NHC INTENSITY FORECAST IS VERY CLOSE TO THE SHIPS MODEL AND SHOWS A LITTLE MORE WEAKENING BY DAY 5 THAN INDICATED IN THE PREVIOUS ADVISORY. NADINE IS NOW MOVING NORTH-NORTHEASTWARD WITH A MOTION OF 015/12 KT. THE STORM IS ENTERING THE BELT OF MID-LATITUDE WESTERLIES...AND IT SHOULD TURN EASTWARD DURING THE NEXT DAY OR TWO. A NORTHEASTWARD TURN IS THEN FORECAST BY DAYS 4 AND 5 AS NADINE APPROACHES A LARGE DEEP-LAYER LOW NEAR THE AZORES. THE TRACK MODELS HAVE SHIFTED SOUTHWARD BEYOND 24 HOURS...LEAVING THE PREVIOUS OFFICIAL FORECAST ON THE NORTHERN EDGE OF THE GUIDANCE ENVELOPE. THE NEW FORECAST HAS BEEN MOVED A LITTLE SOUTHWARD AS WELL...SHOWING A MORE PRONOUNCED DUE-EAST MOTION FOR A TIME. THE NHC TRACK LIES VERY CLOSE TO THE TIGHTLY CLUSTERED GFS...ECMWF...AND MODEL CONSENSUS TVCA. FORECAST POSITIONS AND MAX WINDS INIT 14/2100Z 28.8N 53.4W 60 KT 70 MPH 12H 15/0600Z 30.1N 52.6W 60 KT 70 MPH 24H 15/1800Z 30.9N 50.4W 60 KT 70 MPH 36H 16/0600Z 31.0N 47.5W 60 KT 70 MPH 48H 16/1800Z 31.1N 44.1W 65 KT 75 MPH 72H 17/1800Z 32.5N 37.5W 65 KT 75 MPH 96H 18/1800Z 35.0N 33.5W 65 KT 75 MPH 120H 19/1800Z 37.0N 32.0W 55 KT 65 MPH $$ FORECASTER BERG