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#3589 (Received by flhurricane at: 10:59 PM 02.Aug.2004) TCDAT1 TROPICAL STORM ALEX DISCUSSION NUMBER 11 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT MON AUG 02 2004 DOPPLER RADAR DATA AND RECONNAISSANCE REPORTS INDICATE ALEX HAS DEVELOPED A 10 NMI DIAMETER EYE. A 03/119Z RECON REPORT ALSO CAME IN WITH A SURFACE PRESSURE OF 987 MB. THE HIGHEST WIND REPORTED AT THE 850 MB FLIGHT-LEVEL HAS BEEN 69 KT IN THE SOUTHEAST QUADRANT... WHICH IS CONSISTENT WITH SOME 64+ KT WINDS NOTED IN DOPPLER VELOCITY DATA BEFORE THE DATA BECAME RANGE OBSCURED. THE 69-KT FLIGHT-LEVEL WIND WOULD EQUATE TO ABOUT 56 KT SURFACE WINDS...BUT THE 987 MB PRESSURE IS TYPICAL OF SOME HURRICANES. THE INTENSITY HAS BEEN INCREASED TO 60 KT BASED ON THE CENTRAL PRESSURE...THE SMALL EYE...AND THE ASSUMPTION THAT SOME STRONGER WINDS EXIST IN THE NORTHERN SEMICIRCLE WHERE THE STRONGEST CONVECTION IS OCCURRING. THE INITIAL MOTION IS 040/08. ALEX HAS MADE A SLIGHT TURN TO RIGHT ...BUT IT IS ESSENTIALLY ON THE PREVIOUS FORECAST TRACK. THERE IS SOME DISAGREEMENT AMONG SEVERAL OF THE NHC MODELS. THE 03/00Z INTERPOLATED MODEL TRACKS FROM THE CURRENT POSITION KEEP ALEX WELL OFFSHORE THE NORTH CAROLINA COAST...WHILE THE 02/18Z GFS AND NOGAPS MODEL RUNS MOVE ALEX INLAND NEAR CAPE LOOKOUT NORTH CAROLINA IN ABOUT 18 HOURS. THE 03/00Z UPPER-AIR DATA INDICATES A NORTHERLY 40-45 KT WIND MAXIMUM ON THE BACK SIDE OF THE APPROACHING MID-LEVEL TROUGH OVER THE MISSOURI VALLEY...WHICH WOULD SUGGEST THAT THE TROUGH SHOULD DIG A LITTLE MORE SOUTHWARD BEFORE IT PUSHES EASTWARD. THIS WOULD CAUSE THE MID-LEVEL STEERING FLOW TO BACK SLIGHTLY TO A MORE SOUTH-SOUTHWESTWARD DIRECTION AND HELP TO PULL ALEX A LITTLE MORE NORTHWARD LIKE THE 18Z GFS AND NOGAPS MODELS ARE SUGGESTING. THE OFFICIAL TRACK IS JUST A TAD TO THE LEFT OF THE PREVIOUS TRACK AND SOUTH OF THE 18Z NOGAPS AND GFS SOLUTIONS...BUT BRINGS ALEX VERY CLOSE TO THE OUTER BANKS IN ABOUT 12-18 HOURS. ALEX ONLY HAS ABOUT 12 TO PROBABLY NO MORE THAN 24 HOURS LEFT TO INTENSIFY AS SOUTHWESTERLY SHEAR IS EXPECTED TO SIGNIFICANTLY INCREASE AFTER THAT. BUT THERE IS PLENTY OF WARM WATER AHEAD UNTIL THAT TIME...SO ALEX STILL HAS AN EXCELLENT CHANCE TO BECOME A HURRICANE...AND IT COULD PEAK AROUND 70 KT BETWEEN FORECAST TIMES. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 03/0300Z 32.8N 77.8W 60 KT 12HR VT 03/1200Z 34.1N 76.8W 65 KT 24HR VT 04/0000Z 35.7N 74.3W 65 KT 36HR VT 04/1200Z 37.4N 70.7W 60 KT 48HR VT 05/0000Z 39.9N 64.6W 55 KT...BECOMING EXTRATROPICAL 72HR VT 06/0000Z 43.5N 52.0W 45 KT...EXTRATROPICAL 96HR VT 07/0000Z...ABSORBED BY EXTRATROPICAL LOW |