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| #46426 (Received by flhurricane at: 10:58 PM 16.Sep.2005) TCDAT1 TROPICAL STORM OPHELIA DISCUSSION NUMBER 44 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT FRI SEP 16 2005 A LAST MINUTE RECON REPORT AT 0220Z SUPPORTS WHAT WAS NOTED IN SATELLITE IMAGERY...AND THAT IS THAT THE LOW-LEVEL CIRCULATION CENTER IS LAGGING WELL BEHIND THE MID- AND UPPER-LEVEL CENTERS BY ALMOST 60 NMI. HOWEVER...THE SYSTEM DOES NOT APPEAR TO BE SHEARING APART...BUT RATHER...THE VORTEX IS JUST TILTED DOWNSTREAM BY THE INCREASING SOUTHWESTERLY UPPER-LEVEL FLOW. THE CENTRAL PRESSURE HAS ALSO RISEN TO 998 MB AND THE RECON WINDS IN THE NORTHEAST QUADRANT HAVE ONLY BEEN AROUND 50 KT AT 850 MB. HOWEVER...THE SOUTHEAST QUADRANT HAS NOT YET BEEN SAMPLED...SO I AM HOLDING THE INTENSITY AT 55 KT FOR THIS ADVISORY. THE INITIAL MOTION AND SPEED WAS ORIGINALLY SOMEWHAT UNCERTAIN... BUT THE TIMELY FIX BY THE AIR FORCE RESERVE RECON FLIGHT CREW INDICATES OPHELIA IS NOW MOVING A LITTLE FASTER TO THE NORTHEAST... 040 DEGREES...AT 13 KT. THE NHC MODEL GUIDANCE IS IN EXCELLENT AGREEMENT ON ACCELERATING OPHELIA TO THE NORTHEAST TOWARD THE SOUTHEASTERN COAST OF NOVA SCOTIA IN 24 HOURS...WHICH ALSO KEEPS THE CENTER WELL TO THE SOUTHEAST OF THE NEW ENGLAND STATES. AFTER 24 HOURS...OPHELIA IS EXPECTED TO CONTINUE ACCELERATING TO THE EAST-NORTHEAST ACROSS NEWFOUNDLAND IN 36-48 HOURS AND THEN TURN EASTWARD ACROSS THE FAR NORTH ATLANTIC. THE OFFICIAL FORECAST TRACK IS A LITTLE TO THE RIGHT AND FASTER THAN THE PREVIOUS TRACK. INCREASING SHEAR AND MUCH COOLER WATER IS TAKING ITS TOLL ON OPHELIA NOW. THE 55-KT INITIAL INTENSITY MAY BE A LITTLE GENEROUS GIVEN THE 5 MB RISE IN PRESSURE...BUT SOME STRONGER WINDS MAY EXIST IN THE SOUTHEAST QUADRANT AS A RESULT OF THE INCREASING FORWARD SPEED OF MOTION. THE WIND RADII WERE TRIMMED BACK A LITTLE IN THE NORTHWEST QUADRANT BASED ON A 00Z SHIP REPORT. ALTHOUGH THE CONVECTIVE PATTERN IS DECREASING...INCREASING BAROCLINIC EFFECTS FROM AN APPROACHING VIGOROUS SHORTWAVE TROUGH ARE EXPECTED TO KEEP OPHELIA A POTENT EXTRATROPICAL LOW PRESSURE SYSTEM. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 17/0300Z 37.8N 72.2W 55 KT 12HR VT 17/1200Z 40.0N 70.0W 55 KT...BECOMING EXTRATROPICAL 24HR VT 18/0000Z 43.5N 65.5W 50 KT...EXTRATROPICAL 36HR VT 18/1200Z 46.5N 60.0W 50 KT...EXTRATROPICAL 48HR VT 19/0000Z 48.7N 53.8W 45 KT...EXTRATROPICAL 72HR VT 20/0000Z 52.2N 38.9W 45 KT...EXTRATROPICAL 96HR VT 21/0000Z 55.0N 22.0W 40 KT...EXTRATROPICAL 120HR VT 22/0000Z 61.0N 9.0W 40 KT...EXTRATROPICAL |
