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#3924 (Received by flhurricane at: 10:51 PM 05.Aug.2004) TCDAT1 HURRICANE ALEX DISCUSSION NUMBER 23 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT THU AUG 05 2004 THE EYE OF ALEX CONTINUES TO BECOME LESS DISTINCT AND A 05/2210Z SSMI OVERPASS SUGGESTS THAT THE LOW-LEVEL CIRCULATION IS BEGINNING TO DECOUPLE FROM THE MID- AND UPPER-LEVEL CIRCULATIONS. THE LATEST DVORAK CLASSIFICATIONS FROM TAFB AND SAB ARE 4.0/5.0...AND 4.0/5.5 FROM AFWA. USING AN AVERAGE OF THE T AND CI NUMBERS TO ESTIMATE THE INTENSITY OF WEAKENING SYSTEMS YIELDS ABOUT 75 KT FOR THE ADVISORY INTENSITY. THIS INTENSITY IS ALSO CONSISTENT WITH A 05/2200Z PRESSURE REPORT OF 979.3 MB WHEN THE EYE WENT ALMOST DIRECTLY OVER CANADIAN BUOY 44140. THE INITIAL MOTION ESTIMATE IS 065/39. THE INITIAL POSITION IS BASED A EXTRAPOLATION ALONG THE PREVIOUS FORECAST TRACK AND USING THE SAME SPEED OF 39 KT. THIS IS A TAD BEHIND THE SATELLITE POSITIONS OBTAINED BY TAFB AND SAB...BUT IT IS CONSISTENT WITH THE AFOREMENTIONED BUOY AND SSMI/MICROWAVE POSITIONS. ALEX IS EXPECTED TO TURN MORE WESTWARD AND SLOW SLIGHTLY AS THE CYCLONE GRADUALLY INTERACTS WITH AND IS EVENTUALLY ABSORBED INTO A LARGER EXTRATROPICAL LOW. THIS OFFICIAL TRACK IS JUST AN EXTENSION OF THE PREVIOUS FORECAST TRACK AND IS CLOSE TO THE GLOBAL MODEL CONSENSUS. ALEX IS ALREADY OVER 16-17C SSTS WITH LITTLE CHANGE EXPECTED AHEAD OF THE CYCLONE FOR THE NEXT 24 HOURS. THEREFORE... RAPID TRANSITION INTO AN EXTRATROPICAL LOW PRESSURE SYSTEM IS EXPECTED. COORDINATION WITH THE CANADIAN HURRICANE CENTRE INDICATES THAT RAPID VARIATIONS IN HARBOR WATER LEVELS BETWEEN 12 AM AND 3 AM LOCAL TIME ARE POSSIBLE ALONG THE EASTERN COAST OF THE AVALON PENINSULA... BETWEEN CAPE RACE AND CAPE SAINT FRANCIS...AND ALONG THE EASTERN SIDE OF THE BONAVISTA PENINSULA AND POSSIBLY CONCEPTION BAY. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 06/0300Z 44.9N 47.4W 75 KT...BECOMING EXTRATROPICAL 12HR VT 06/1200Z 46.4N 40.1W 60 KT...EXTRATROPICAL 24HR VT 07/0000Z 47.1N 29.9W 50 KT...EXTRATROPICAL 36HR VT 07/1200Z 47.0N 20.0W 45 KT...EXTRATROPICAL 48HR VT 08/0000Z...ABSORBED INTO EXTRATROPICAL LOW |