000 WTNT41 KNHC 262035 TCDAT1 HURRICANE DANIELLE DISCUSSION NUMBER 21 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062010 500 PM AST THU AUG 26 2010 SATELLITE IMAGERY THIS AFTERNOON INDICATES THAT DANIELLE HAS DEVELOPED A WELL-DEFINED 20 NM WIDE EYE WITH CLOUD TOPS TO -75C IN THE NORTHWESTERN EYEWALL. SATELLITE INTENSITY ESTIMATES AT 18Z WERE 90 KT FROM TAFB AND SAB...AND SINCE THAT TIME THE SATELLITE APPEARANCE OF THE HURRICANE HAS IMPROVED. THUS...THE INITIAL INTENSITY IS INCREASED TO 95 KT. THE CIRRUS IS FAIR TO GOOD IN ALL DIRECTIONS EXCEPT TO THE SOUTH. THE INITIAL MOTION IS 315/13. FOR THE NEXT 36 HR...DANIELLE SHOULD BE STEERED GENERALLY NORTHWESTWARD BY A LOW/MID-LEVEL RIDGE PASSING TO THE NORTH AND NORTHEAST OF THE HURRICANE. AFTER THAT...A LARGE MID/UPPER-LEVEL TROUGH MOVING THROUGH THE NORTHEASTERN UNITED STATES AND THE CANADIAN MARITIMES IS EXPECTED TO CAUSE DANIELLE TO RECURVE TOWARD THE NORTHEAST. WITH TWO EXCEPTIONS...THE TRACK MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THIS SCENARIO. THOSE EXCEPTIONS ARE THE NOGAPS AND GFDN...WHICH FORECAST DANIELLE TO MOVE NORTHWARD AND THEN STALL NORTH OF BERMUDA. THE NEW TRACK FORECAST FOLLOWS THE RECURVATURE SCENARIO AND CALLS FOR DANIELLE TO GRADUALLY ACCELERATE TOWARD THE NORTHEAST AFTER 48 HR. THE NEW TRACK IS STILL TO THE LEFT AND SLOWER THAN THE BULK OF THE DYNAMICAL MODELS...AND ADDITIONAL ADJUSTMENTS MAY BE NEEDED ON THE NEXT ADVISORY. ANALYSES FROM CIMSS AT THE UNIVERSITY OF WISCONSIN SUGGEST THAT DANIELLE IS EXPERIENCING 10-15 KT OF SOUTHERLY VERTICAL WIND SHEAR. THE HURRICANE SHOULD CONTINUE IN A LIGHT/MODERATE SHEAR ENVIRONMENT FOR 36-48 HR BEFORE ENCOUNTERING STRONGER SHEAR ASSOCIATED WITH THE UPPER-LEVEL TROUGH. ALL INTENSITY GUIDANCE FORECAST STRENGTHENING FOR 24 HR OR SO AND THE INTENSITY FORECAST FOLLOWS THAT SCENARIO...WITH A PEAK INTENSITY OF 105 KT IN 24 HR. AFTER 48 HR...INCREASING SHEAR AND DECREASING SEA SURFACE TEMPERATURES SHOULD CAUSE STEADY WEAKENING. EXTRATROPICAL TRANSITION MAY BE UNDERWAY BY 120 HR...BUT IS EXPECTED TO BE COMPLETED AFTER THE END OF THE FORECAST PERIOD. FORECAST POSITIONS AND MAX WINDS INITIAL 26/2100Z 25.2N 57.0W 95 KT 12HR VT 27/0600Z 26.0N 58.3W 95 KT 24HR VT 27/1800Z 27.3N 60.0W 100 KT 36HR VT 28/0600Z 28.6N 61.1W 105 KT 48HR VT 28/1800Z 30.2N 61.2W 105 KT 72HR VT 29/1800Z 34.0N 59.5W 95 KT 96HR VT 30/1800Z 37.5N 56.5W 80 KT 120HR VT 31/1800Z 39.5N 51.0W 65 KT $$ FORECASTER BEVEN