000 WTNT41 KNHC 020254 TCDAT1 HURRICANE OPHELIA DISCUSSION NUMBER 38 NWS NATIONAL HURRICANE CENTER MIAMI FL AL162011 1100 PM AST SAT OCT 01 2011 DURING ITS SECOND LIFETIME...OPHELIA HAS BEEN AN OVERACHIEVER AND HAS CONTINUED TO INTENSIFY. THE BERMUDA RADAR EARLIER INDICATED THAT THE EYEWALL WAS QUITE STRONG WITH A CLOSED PRESENTATION. MORE RECENTLY...SATELLITE IMAGES SHOW A WARM WELL-DEFINED EYE...A MORE SYMMETRIC CLOUD PATTERN...AND COOLING CLOUD TOPS IN THE EYEWALL. SUBJECTIVE DVORAK DATA-T VALUES WERE NEAR 115 KT AT 00Z...WITH CIMSS ADT VALUES REACHING 122 KT. A BLEND OF THESE DATA GIVES AN INITIAL WIND SPEED OF 120 KT. WEAKENING SHOULD BEGIN SOON AS THE HURRICANE MOVES OVER COOLER SSTS...AND THE DECREASE IN STRENGTH SHOULD BE QUITE RAPID BY MIDDAY TOMORROW DUE TO AN INCREASE IN SHEAR AND OPHELIA CROSSING THE NORTH WALL OF THE GULF STREAM. THE NHC FORECAST IS CLOSE TO THE LGEM MODEL AND THE PREVIOUS FORECAST. THE INITIAL MOTION IS ABOUT THE SAME AS BEFORE...010/23. A GRADUALLY ACCELERATING TRACK TOWARD THE NORTH-NORTHEAST SHOULD BEGIN EARLY SUNDAY AS THE CYCLONE MOVES BETWEEN A DEEP TROUGH ALONG THE U.S. EAST COAST AND A RIDGE OVER THE CENTRAL ATLANTIC. THE HURRICANE WILL LIKELY TURN TOWARD THE NORTHEAST BY MONDAY MORNING AS IT MOVES AROUND THE NORTHERN PORTION OF THE RIDGE. ALMOST ALL OF THE GLOBAL MODELS SHOW OPHELIA NEAR OR JUST TO THE SOUTH OF NEWFOUNDLAND IN ABOUT 36 HOURS...AND THE OFFICIAL FORECAST HAS BEEN SHIFTED LEFTWARD AND LIES BETWEEN THE GFS AND ECMWF MODELS. IT IS WORTH NOTING THAT OF THE GENERALLY RELIABLE GUIDANCE...ONLY THE ECMWF KEEPS THE CENTER OFFSHORE. HOWEVER...THE STORM WILL LIKELY BE RAPIDLY TRANSITIONING TO AN EXTRATROPICAL CYCLONE BY THAT TIME...WITH THE STRONGEST WINDS OCCURRING AT SOME DISTANCE SOUTHEAST OF THE CENTER. THE WIND RADII HAVE BEEN ADJUSTED BASED ON A 0046 UTC ASCAT PASS. FORECAST POSITIONS AND MAX WINDS INIT 02/0300Z 33.8N 62.2W 120 KT 140 MPH 12H 02/1200Z 37.4N 61.1W 110 KT 125 MPH 24H 03/0000Z 42.5N 59.0W 85 KT 100 MPH 36H 03/1200Z 46.5N 53.3W 60 KT 70 MPH 48H 04/0000Z 49.5N 44.0W 50 KT 60 MPH...POST-TROP/EXTRATROP 72H 05/0000Z 53.0N 22.5W 40 KT 45 MPH...POST-TROP/EXTRATROP 96H 06/0000Z...DISSIPATED $$ FORECASTER BLAKE/BRENNAN