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#534793 (Received by flhurricane at: 10:35 PM 16.Aug.2012) TCDAT3 TROPICAL STORM GORDON DISCUSSION NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL AL082012 1100 PM AST THU AUG 16 2012 ALTHOUGH THE CONVECTION IS NOT VERY DEEP...SATELLITE IMAGES SHOW THAT THE CLOUD PATTERN HAS BECOME SYMMETRIC WITH THE CENTER OF THE CYCLONE EMBEDDED WITHIN A CIRCULAR AREA OF THE STRONGEST CONVECTION. A WELL-DEFINED CYCLONICALLY-CURVED BAND IS WRAPPING AROUND THE NORTH AND EAST SIDES OF THE CIRCULATION. T-NUMBERS FROM BOTH TAFB AND SAB ARE 4.0 AND 3.0 RESPECTIVELY. AN AVERAGE OF THESE TWO ESTIMATES SUGGESTS AN INITIAL INTENSITY OF 60 KNOTS. GORDON ONLY HAS A DAY OR SO TO BECOME A HURRICANE BEFORE IT MOVES OVER COOLER WATERS AND ENCOUNTERS STRONG SHEAR. A GRADUAL WEAKENING SHOULD THEN BEGIN...BUT GORDON IS FORECAST TO REMAIN A TROPICAL STORM BY THE TIME IT MOVES THROUGH THE AZORES IN 3 DAYS. ONCE GORDON MOVE EAST OF THE AZORES...IT SHOULD ACQUIRE EXTRATROPICAL CHARACTERISTICS. GORDON IS MOVING TOWARD THE EAST OR 085 DEGREES AT 15 KNOTS...WELL EMBEDDED WITHIN THE MID-LATITUDE WESTERLIES. SINCE THE STEERING CURRENTS ARE FORECAST BY THE GLOBAL MODELS TO REMAIN WELL ESTABLISHED...GORDON SHOULD CONTINUE TO MOVE EASTWARD FOR THE NEXT THREE DAYS WITH NO SIGNIFICANT CHANGE IN FORWARD SPEED. TRACK MODELS ARE IN REMARKABLY GOOD AGREEMENT IN BRINGING THE CYCLONE EASTWARD THROUGH THE AZORES. MODELS ALSO SHOW A GRADUAL TURN TOWARD THE NORTHEAST BY 72 HOURS AS A SHORTWAVE TROUGH AMPLIFIES TO THE WEST OF THE CYCLONE. THE OFFICIAL FORECAST IS IN THE MIDDLE OF THE GUIDANCE ENVELOPE AND BRINGS GORDON THROUGH THE AZORES IN ABOUT 3 DAYS. FORECAST POSITIONS AND MAX WINDS INIT 17/0300Z 34.6N 50.3W 60 KT 70 MPH 12H 17/1200Z 34.9N 47.7W 65 KT 75 MPH 24H 18/0000Z 34.8N 43.5W 70 KT 80 MPH 36H 18/1200Z 34.5N 39.5W 65 KT 75 MPH 48H 19/0000Z 34.5N 35.9W 60 KT 70 MPH 72H 20/0000Z 36.5N 28.5W 50 KT 60 MPH 96H 21/0000Z 39.0N 21.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 120H 22/0000Z 41.0N 15.0W 40 KT 45 MPH...POST-TROP/EXTRATROP $$ FORECASTER AVILA |