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#35982 (Received by flhurricane at: 10:34 AM 28.Jul.2005) TCDAT1 TROPICAL STORM FRANKLIN DISCUSSION NUMBER 29 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 AM EDT THU JUL 28 2005 THE EARLIER BURST OF CENTRAL DEEP CONVECTION HAS BEEN ON THE WANE THE PAST FEW HOURS. A 28/0953Z HI-RES QUIKSCAT OVERPASS INDICATED THAT THE LOW-LEVEL CENTER HAD BEEN IN THE MIDDLE OF THE SMALL CDO... SUGGESTING THAT FRANKLIN MAY HAVE REACHED NEAR 50 KT INTENSITY BETWEEN 06-09Z. THAT INTENSITY IS ALSO SUPPORTED BY AN AMSU INTENSITY ESTIMATE FROM NESDIS CIRA OF 47 KT AND 998 MB AT 0807Z... AND A 12Z TAFB SATELLITE INTENSITY ESTIMATE OF T3.5/55 KT. HOWEVER ...SINCE THE CONVECTION HAS BEEN DECEASING AND BECOME LESS ORGANIZED...THE INTENSITY WILL BE HELD AT 45 KT FOR THE TIME BEING. THE WIND RADII WERE TRIMMED BACK SLIGHTLY BASED ON QUIKSCAT DATA. THE INITIAL MOTION ESTIMATE IS NOW 020/09. IT APPEARS THAT FRANKLIN IS FINALLY STARTING TO MAKE THE LONG AWAITED TURN TO THE NORTHEAST. THIS TREND SHOULD CONTINUE WITH GRADUAL ACCELERATION AS THE CYCLONE GETS CAUGHT UP IN THE INCREASING DEEP-LAYER SOUTHWESTERLY STEERING FLOW AHEAD OF AN ADVANCING MID-LATITUDE FRONTAL SYSTEM CURRENTLY LOCATED JUST OFFSHORE THE NORTHEAST U.S. COAST. THE OFFICIAL FORECAST TRACK IS SLIGHTLY TO THE LEFT OF THE PREVIOUS FORECAST THROUGH 24 HOURS AND THEN COMES BACK ON TRACK AFTER THAT. THIS IS CONSISTENT WITH THE UKMET AND NOGAPS MODELS...WHICH HAVE BEEN THE OVERALL BEST PERFORMING MODELS WITH THIS SYSTEM. WATER VAPOR IMAGERY SUGGESTS THAT THERE IS STILL ENOUGH OF A MID-LEVEL RIDGE PROTRUDING NORTHWESTWARD TO THE NORTHEAST OF FRANKLIN...WHICH HAS TEMPORARILY INCREASED THE SHEAR NOW THAT THE UPPER-LEVEL FLOW HAS BECOME SOUTHWESTERLY. I WOULD SUSPECT THAT THIS SHEAR PATTERN AND CURRENT DISRUPTION OF THE CENTRAL DEEP CONVECTION WILL BE SHORT-LIVED ONCE FRANKLIN MAKES THE TURN AND BEGINS TO ACCELERATE TO THE NORTHEAST IN ANOTHER 6 HOURS OR SO. RECENT SHIP OBS ALSO REVEAL THAT THE 26C SST ISOTHERM ACTUALLY EXTENDS UP TO 40N LATITUDE...ABOUT 2 DEGREES NORTH OF WHAT THE SHIPS INTENSITY MODEL IS INDICATING. AS SUCH...THERE REMAINS ABOUT ANOTHER 24 HOURS OR SO OF OPPORTUNITY FOR FRANKLIN TO STRENGTHEN WHILE THE VERTICAL REMAINS LOW. AFTERWARDS...THE CYCLONE WILL MOVE OVER MUCH COLDER WATER AND RAPIDLY WEAKEN. IF FRANKLIN MAKES A SLOWER TURN TO THE NORTHEAST THAN CURRENTLY FOREAST...THEN TROPICAL STORM-FORCE WINDS COULD POSSIBLY BRUSH EXTREME SOUTHEASTERN NEWFOUNDLAND IN 60-72 HOURS. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 28/1500Z 36.2N 69.0W 45 KT 12HR VT 29/0000Z 37.5N 67.5W 50 KT 24HR VT 29/1200Z 39.3N 64.9W 55 KT 36HR VT 30/0000Z 41.1N 61.6W 45 KT...BECOMING EXTRATROPICAL 48HR VT 30/1200Z 43.0N 57.7W 35 KT...EXTRATROPICAL 72HR VT 31/1200Z 47.0N 48.0W 30 KT...EXTRATROPICAL 96HR VT 01/1200Z...ABSORBED BY FRONTAL SYSTEM |