ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM HURRICANE GABRIELLE DISCUSSION NUMBER 25 NATIONAL WEATHER SERVICE MIAMI FL 5 PM EDT MON SEP 17 2001 GABRIELLE REMAINS A FAIRLY IMPRESSIVE SYSTEM DESPITE THE SOUTHWESTERLY UPPER-LEVEL SHEAR. IN FACT...VISIBLE IMAGERY DURING THE PAST FEW HOURS SUGGESTS THAT A BANDING EYE FEATURE MAY BE TRYING TO FORM AS MODERATE CONVECTION HAS WRAPPED ABOUT THREE-FOURTHS OF THE WAY AROUND THE LOW-LEVEL CENTER. OUTFLOW REMAINS QUITE GOOD IN THE NORTH SEMICIRCLE...BUT IS ALMOST NON-EXISTENT TO THE SOUTH. THE INITIAL MOTION ESTIMATE IS 060/15. GABRIELLE HAS RETURNED TO THE PREVIOUS EAST-NORTHEASTWARD BASE COURSE. THE NHC MODEL GUIDANCE IS IN MUCH BETTER AGREEMENT ON TAKING GABRIELLE OFF IN A GENERAL NORTHEASTWARD DIRECTION. THE UKMET IS NOW IN THE MIDDLE OF THE MODEL PACK AND NO LANGER TAKES THE CYCLONE ACROSS SOUTHEAST NEWFOUNDLAND. THIS APPEARS VERY REASONABLE GIVEN THE LONG FETCH OF MID- TO UPPER-LEVEL WESTERLY FLOW ACROSS THE NORTHEAST U.S. AND EASTERN CANADA. IN 24 TO 36 HOURS...GABRIELLE IS FORECAST TO GET PICKED UP BY A MID-LATITUDE TROUGH AND BECOME AN EXTRATROPICAL LOW PRESSURE SYSTEM. AS LONG AS DEEP CONVECTION REMAINS NEAR THE LOW-LEVEL CIRCULATION CENTER...GABRIELLE WILL REMAIN A WARM-CORE SYSTEM AND COULD EVEN STRENGTHEN A LITTLE MORE. HOWEVER...BY THE TIME THE CYCLONE REACHES 40N LATITUDE IN ABOUT 24 HOURS...SSTS WILL DECREASE SHARPLY BELOW 22C AND THAT SHOULD AID THE TRANSITION TO AN EXTRATROPICAL SYSTEM AND BRING ABOUT MORE SIGNIFICANT WEAKENING. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 17/2100Z 36.5N 64.2W 70 KTS 12HR VT 18/0600Z 37.8N 62.0W 70 KTS 24HR VT 18/1800Z 39.9N 58.8W 65 KTS...BECOMING EXTRATROPICAL 36HR VT 19/0600Z 41.9N 56.1W 60 KTS...EXTRATROPICAL 48HR VT 19/1800Z 45.3N 50.9W 55 KTS...EXTRATROPICAL 72HR VT 20/1800Z 49.5N 42.5W 50 KTS...EXTRATROPICAL NNNN