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#3435 (Received by flhurricane at: 10:56 PM 01.Aug.2004) TCDAT1 TROPICAL STORM ALEX DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT SUN AUG 01 2004 RECONNAISSANCE FLIGHTS THIS EVENING INDICATE THAT THE INTENSITY HAS CHANGED LITTLE. THE MID-LEVEL CORE REGION...HOWEVER...HAS BECOME A LITTLE BETTER ORGANIZED BASED ON DOPPLER RADAR DATA...BUT THE CYCLONE REMAINS UNDER NORTH TO NORTHEASTERLY UPPER-LEVEL SHEAR. THIS HAS PREVENTED THE WELL-DEFINED MID-LEVEL CIRCULATION NOTED IN RADAR DATA FROM ALIGNING WITH ANY OF THE MANY LOW-LEVEL SWIRLS THAT CONTINUE TO POP OUT THE NORTH SIDE OF THE CONVECTION. THE INITIAL INTENSITY REMAINS AT 35 KT BASED ON 45-KT FLIGHT-LEVEL WINDS. THE INITIAL MOTION REMAINS STATIONARY. 00Z UPPER-AIR DATA INDICATE THE MID-LEVEL RIDGE/HIGH OVER THE SOUTHEASTERN U.S. AND EXTENDING EASTWARD TO NEAR BERMUDA HAS REMAINED INTACT. HOWEVER...THERE ARE SOME INDICATIONS THAT THE RIDGE AXIS ACROSS NORTH AND SOUTH CAROLINA IS BEGINNING TO WEAKEN. THIS MAY ALLOW FOR ALEX TO MAKE A SLOW NORTHWARD DRIFT ON MONDAY BEFORE A MID- TO UPPER-LEVEL TROUGH CURRENTLY OVER THE MISSOURI VALLEY DIGS EAST-SOUTHEASTWARD AND BEGINS TO MOVE ALEX QUICKLY TO THE NORTHEAST BY 24-36 HOURS. THE VAST MAJORITY OF THE NHC MODEL GUIDANCE MOVES ALEX INLAND OVER THE SOUTHEAST U.S. HOWEVER...THE CENTER OF ALEX MAY STILL GET UNCOMFORTABLY CLOSE TO THE COAST IN 24-36 HOURS BEFORE IT GETS CAUGHT UP BY THE APPROACHING TROUGH AND IS CARRIED OUT TO SEA. GIVEN THE STATIONARY MOTION EXPECTED DURING THE NEXT 6-12 HOURS... THE PREVIOUS FORECAST TRACK WAS SLOWED...BUT OTHER THAN THAT NO OTHER SIGNIFICANT CHANGES WERE MADE. THIS IS CONSISTENT WITH THE GUNA MODEL CONSENSUS. LATEST SATELLITE IMAGERY SUGGESTS THAT THE NORTHERLY UPPER-LEVEL SHEAR THAT HAS BEEN HINDERING THE FORWARD MOTION AND THE INTENSIFICATION PROCESS MAY BE DECREASING AS INDICATED BY CIRRUS CLOUDS BEGINNING TO FAN OUT SLIGHTLY IN THE NORTHERN SEMICIRCLE. SOME SIGNIFICANT STRENGTHENING COULD OCCUR MONDAY AND MONDAY NIGHT AS ALEX BEGINS TO MOVE NORTHEASTWARD AND PASSES OVER THE GULFSTREAM UNDER DECREASING VERTICAL SHEAR. BY 48 HOURS...VERTICAL SHEAR IS EXPECTED TO INCREASE FROM THE SOUTHWEST AND ESSENTIALLY CAP THE INTENSIFICATION PROCESS. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 02/0300Z 31.5N 79.2W 35 KT 12HR VT 02/1200Z 32.2N 78.7W 40 KT 24HR VT 03/0000Z 33.1N 77.5W 45 KT 36HR VT 03/1200Z 34.7N 74.9W 50 KT 48HR VT 04/0000Z 36.7N 71.6W 50 KT 72HR VT 05/0000Z 42.0N 61.5W 45 KT...BECOMING EXTRATROPICAL 96HR VT 06/0000Z 48.5N 49.0W 45 KT...EXTRATROPICAL 120HR VT 07/0000Z...ABSORBED BY EXTRATROPICAL LOW |