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#6395 (Received by flhurricane at: 10:44 PM 28.Aug.2004) TCDAT2 TROPICAL STORM GASTON DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT SAT AUG 28 2004 A U.S. AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT MEASURED 60 KT WINDS AT 1500 FT FLIGHT LEVEL TO THE SOUTHWEST OF THE CENTER AND MEASURED A CENTRAL PRESSURE OF 994 MB AND ALSO REPORTED A 35 N MI DIAMETER EYE WITH SOME OPEN AREAS. BOTH CHARLESTON AND WILMINGTON RADARS SHOW AN EYE-TYPE FEATURE EXCEPT OPEN TO THE SOUTH. THE WIND SPEED IS INCREASED TO 55 KT BASED ON THE ABOVE. WITH LIGHT VERTICAL SHEAR AND WARM SSTS...BOTH THE SHIPS AND GFDL MODELS BRING GASTON TO ABOUT 65 KT BEFORE LANDFALL. THE OFFICIAL INTENSITY FORECAST FOLLOWS THIS GUIDANCE. THE INITIAL MOTION IS 330/03 BASED ON RECON...RADAR AND SATELLITE FIXES. THE TRACK GUIDANCE CONTINUES THE SAME SCENARIO OF A TURN TOWARD THE NORTH AND THEN NORTHEAST IN RESPONSE TO AN ADVANCING SHORT WAVE TROUGH IN THE WESTERLIES. THE OFFICIAL TRACK FORECAST IS THE SAME AS THE PREVIOUS ADVISORY...EXCEPT A LITTLE FASTER... THROUGH 24 HOURS. AFTER 24 HOURS...THE OFFICIAL FORECAST IS ADJUSTED TO THE LEFT OF THE PREVIOUS ADVISORY AND IS ALSO FASTER IN AGREEMENT WITH A CONSENSUS OF THE GLOBAL TRACK MODELS. RECON OBSERVATIONS SHOW THAT THE RADIUS OF 35 KT WINDS IS ONLY ABOUT 50 N MI OR LESS IN ALL QUADRANTS. THE RADII EAST OF THE CENTER ARE FORECAST TO EXPAND TO 75 N MI AS GASTON MOVES NORTHWARD. FORECASTER LAWRENCE FORECAST POSITIONS AND MAX WINDS INITIAL 29/0300Z 31.7N 79.2W 55 KT 12HR VT 29/1200Z 32.3N 79.5W 65 KT 24HR VT 30/0000Z 33.6N 79.7W 55 KT...INLAND 36HR VT 30/1200Z 35.1N 79.0W 30 KT...INLAND 48HR VT 31/0000Z 36.7N 77.0W 30 KT...INLAND 72HR VT 01/0000Z 41.0N 70.0W 30 KT...EXTRATROPICAL 96HR VT 02/0000Z 45.0N 59.0W 30 KT...EXTRATROPICAL 120HR VT 03/0000Z 47.0N 46.0W 30 KT...EXTRATROPICAL |