000 WTNT41 KNHC 300258 TCDAT1 HURRICANE OPHELIA DISCUSSION NUMBER 30 NWS NATIONAL HURRICANE CENTER MIAMI FL AL162011 1100 PM AST THU SEP 29 2011 OPHELIA IS STRENGTHENING WITH AN EYE FEATURE OCCASIONALLY APPARENT ON BOTH INFRARED AND NIGHT-VISIBLE SATELLITE IMAGES. ALTHOUGH THERE IS SOME TILT ON THE LATEST MICROWAVE PASSES WITH THE LOW-LEVEL CENTER A BIT TO THE WEST OF THE MID-LEVEL CENTER...A SOLID EYEWALL HAS FORMED. SATELLITE INTENSITY ESTIMATES WERE 65 KT AND 77 KT FROM SAB/TAFB...AND GIVEN THE WELL-DEFINED INNER CORE...THE INITIAL WINDS WILL BE INCREASED TO 75 KT ON THIS ADVISORY. WATER VAPOR IMAGES SHOW A LARGE FETCH OF UPPER-LEVEL WESTERLY WINDS HEADED TOWARD THE TROPICAL CYCLONE. HOWEVER...GLOBAL MODEL INSIST THAT THESE STRONG WINDS WILL BE DIVERTED AROUND THE CIRCULATION OF THE HURRICANE AND NOT IMPACT OPHELIA DUE TO A BUILDING UPPER-LEVEL RIDGE. SINCE THE WATERS STAY WARM FOR AT LEAST TWO DAYS AND BOTH THE SHIPS MODEL AND LARGE-SCALE GLOBAL MODEL FIELDS FORECAST DECREASING SHEAR VALUE...THE NHC FORECAST IS RAISED FROM THE PREVIOUS ONE.. THE NEW FORECAST IS BELOW THE HWRF/GFDL CONSENSUS...WHICH SHOW THE CYCLONE AT THE THRESHOLD OF MAJOR HURRICANE STATUS IN A FEW DAYS. THE INITIAL MOTION IS ABOUT THE SAME AS BEFORE...335/8. THERE IS NOT A LOT OF CHANGE TO REPORT IN THE MODELS FOR THE FIRST COUPLE OF DAYS WITH GOOD AGREEMENT ON A GRADUALLY ACCELERATING AND BENDING TRACK TOWARD THE NORTH AND NORTH-NORTHEAST. THE NHC FORECAST DURING THAT TIME IS BASICALLY AN UPDATE OF THE PREVIOUS ADVISORY. AFTER RECURVATURE...HOWEVER...THE MODEL GUIDANCE HAS SHIFTED LEFTWARD DUE TO A STRONGER RIDGE OVER THE CENTRAL ATLANTIC. THE NHC FORECAST IS SHIFTED TO THE WEST AFTER DAY 2 AND IS CLOSE TO A BLEND OF THE ECMWF AND GFS MODELS. GLOBAL MODELS INDICATE THAT OPHELIA WILL BE ABSORBED BY A FRONTAL SYSTEM IN ABOUT 5 DAYS. FORECAST POSITIONS AND MAX WINDS INIT 30/0300Z 21.9N 62.3W 75 KT 85 MPH 12H 30/1200Z 23.2N 62.8W 80 KT 90 MPH 24H 01/0000Z 25.7N 63.3W 85 KT 100 MPH 36H 01/1200Z 28.8N 63.1W 90 KT 105 MPH 48H 02/0000Z 32.8N 62.3W 90 KT 105 MPH 72H 03/0000Z 43.5N 58.5W 70 KT 80 MPH 96H 04/0000Z 52.0N 43.5W 45 KT 50 MPH...POST-TROP/EXTRATROP 120H 05/0000Z...ABSORBED $$ FORECASTER BLAKE