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#45449 (Received by flhurricane at: 5:08 AM 12.Sep.2005) TCDAT1 HURRICANE OPHELIA DISCUSSION NUMBER 24 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 AM EDT MON SEP 12 2005 THE LAST RECON FIX AT 06Z MEASURED A CENTRAL PRESSURE OF 985 MB... A LITTLE HIGHER THAN BEFORE... AND MAXIMUM 700 MB FLIGHT LEVEL WINDS DURING THE PAST SEVERAL HOURS WERE 78 KT IN THE NORTHWESTERN QUADRANT. HOWEVER... IT IS NOT CERTAIN THAT THESE WINDS ARE MIXING DOWN TO THE SURFACE AS MUCH AS THE AVERAGE REDUCTION WOULD DICTATE. SINCE THE PRESSURE HAS BEEN RISING AND THE SATELLITE APPEARANCE NOT ANY MORE IMPRESSIVE... THE ADVISORY INTENSITY IS KEPT AT 65 KT. THE INTENSITY FORECAST AND REASONING ARE ESSENTIALLY THE SAME AS THE PREVIOUS ADVISORY. THE SHIPS MODEL NO LONGER FORECASTS THE WEAKENING THAT IT HAD PREVIOUSLY AND IS NOW MORE SUPPORTIVE OF THE MINIMAL CHANGES IN INTENSITY SHOWN IN THE OFFICIAL FORECAST THROUGH 72 HOURS... UNTIL WEAKENING AND EVENTUAL EXTRATROPICAL TRANSITION OVER COOLER WATERS FARTHER NORTHEAST. CONSECUTIVE RECON FIXES THROUGH 06Z INDICATED AN ESTIMATED INITIAL MOTION OF 270/4. OPHELIA HAS COMPLETED A SMALL CLOCKWISE LOOP AND IS BACK WHERE IT WAS ABOUT 48 HOURS AGO. WHILE THE TRACK FORECAST REASONING HAS NOT SIGNIFICANTLY CHANGED... SOME OF THE MODELS ARE PROVIDING NEW AND DIVERGENT SOLUTIONS. NONE OF THE RELIABLE DYNAMICAL MODELS HAVE BEEN IMMUNE FROM SIGNIFICANT TRACK FORECAST SHIFTS DURING THE PAST DAY OR TWO IN THIS VERY DIFFICULT SCENARIO. THE LATEST RUNS INCLUDE THE GFDL SHIFTING BACK TO THE EAST CLOSER TO THE PREVIOUS OFFICIAL FORECAST. HOWEVER...THE UKMET AND ESPECIALLY THE NOGAPS NOW SUGGEST THAT OPHELIA WILL NOT GET PICKED UP BY THE NEXT MIDLATITUDE TROUGH EXPECTED TO APPROACH THE EAST COAST OF THE U.S. IN ABOUT THREE DAYS. AS A RESULT THESE MODELS FORECAST OPHELIA TO STILL BE NOT FAR OFF THE COAST OF THE CAROLINAS 4-5 DAYS FROM NOW. EVEN THOUGH NOGAPS IS A CREDIBLE MODEL... SINCE THE NOGAPS SOLUTION IS A NEW ONE I AM NOT READY TO MAKE SIGNIFICANT ADJUSTMENTS TO THE OFFICIAL FORECAST. ACCOUNTING FOR THE POSSIBILITY THAT NOGAPS AND UKMET COULD BE AT LEAST PARTIALLY CORRECT... THE OFFICIAL FORECAST IS SLOWER THAN THE PREVIOUS ADVISORY BUT IS ALONG THE SAME PATH... ANTICIPATING A SLOW AND GRADUAL TURN TO THE NORTH AND EVENTUALLY NORTHEAST DURING THE NEXT FIVE DAYS. FORECASTER KNABB FORECAST POSITIONS AND MAX WINDS INITIAL 12/0900Z 31.3N 76.7W 65 KT 12HR VT 12/1800Z 31.4N 77.2W 65 KT 24HR VT 13/0600Z 31.9N 77.5W 65 KT 36HR VT 13/1800Z 32.5N 77.6W 70 KT 48HR VT 14/0600Z 33.3N 77.5W 70 KT 72HR VT 15/0600Z 35.5N 76.0W 70 KT 96HR VT 16/0600Z 38.5N 72.5W 55 KT 120HR VT 17/0600Z 42.0N 68.0W 45 KT...EXTRATROPICAL |