000 WTNT44 KNHC 240901 TCDAT4 TROPICAL STORM NADINE DISCUSSION NUMBER 47 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142012 500 AM AST MON SEP 24 2012 DEEP CONVECTION HAS INCREASED SOME DURING THE PAST 6 HOURS...AND SHEAR PATTERN SATELLITE INTENSITY ANALYSES...SCATTEROMETER DATA... AND PRESSURE REPORTS FROM NEARBY BUOY 41676 INDICATE NADINE HAS WEAKENED SLIGHTLY. NADINE IS FINALLY ON THE MOVE AND THE INITIAL MOTION ESTIMATE 295/05 KT. THE TRACK FORECAST REASONING REMAINS UNCHANGED FROM THE PREVIOUS ADVISORY. A DEEP-LAYER RIDGE CURRENTLY LOCATED TO THE NORTHWEST OF NADINE IS FORECAST TO EVOLVE INTO YET ANOTHER HIGH-OVER-LOW BLOCKING PATTERN FOR THE NEXT SEVERAL DAYS. THE RESULT IS EXPECTED TO BE A WEAK STEERING PATTERN THAT WILL FORCE NADINE ON A WEST TO SOUTHWESTWARD TRACK FOR THE NEXT 72 HORUS...BEFORE TURNING NORTHWESTWARD AND THEN NORTHWARD AROUND THE WESTERN PORTION OF THE RIDGE. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS ADVISORY ND CLOSELY FOLLOWS THE DYNAMICAL MODEL CONSENSUS. DRY AIR ENTRAINMENT...COLD WATER UPWELLING...AND MODERATE SOUTHWESTERLY SHEAR ARE EXPECTED TO INHIBIT STRENGTHENING FOR THE NEXT 24-36 HOURS. AFTER THAT...DECREASING SHEAR COMBINED WITH WARMER SSTS SHOULD ALLOW FOR SOME MODEST INTENSIFICATION. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO PREVIOUS ADVISORY AND IS CLOSE TO INTENSITY CONSENSUS MODELS IV15 AND IVCN. FORECAST POSITIONS AND MAX WINDS INIT 24/0900Z 31.4N 26.9W 45 KT 50 MPH 12H 24/1800Z 31.6N 27.9W 45 KT 50 MPH 24H 25/0600Z 31.7N 29.2W 45 KT 50 MPH 36H 25/1800Z 31.5N 30.3W 50 KT 60 MPH 48H 26/0600Z 30.9N 31.1W 55 KT 65 MPH 72H 27/0600Z 29.5N 32.0W 60 KT 70 MPH 96H 28/0600Z 30.0N 34.0W 65 KT 75 MPH 120H 29/0600Z 33.0N 35.5W 65 KT 75 MPH $$ FORECASTER STEWART