000 WTNT45 KNHC 070244 TCDAT5 TROPICAL DEPRESSION EMILY DISCUSSION NUMBER 15 NWS NATIONAL HURRICANE CENTER MIAMI FL AL052011 1100 PM EDT SAT AUG 06 2011 AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT THIS AFTERNOON FOUND 1000-FT FLIGHT-LEVEL WINDS AS HIGH AS 48 KT IN THE SOUTHERN QUADRANT OF THE LOW-LEVEL CIRCULATION OF EMILY. HOWEVER...THESE WINDS WERE OCCURRING NEAR ISOLATED SMALL CONVECTIVE CELLS AND WERE NOT CONSIDERED TO BE REPRESENTATIVE OF THE STORM-SCALE CIRCULATION. HOWEVER...OTHER FLIGHT-LEVEL AND SFMR SURFACE WIND DATA INDICATE THAT EMILY IS A SOLID 30-KT DEPRESSION. THE INITIAL MOTION ESTIMATE IS NORTHWARD OR 360/07 KT. EMILY IS FORECAST TO MOVE SLOWLY NORTHWARD TONIGHT AND GRADUALLY TURN TOWARD THE NORTHEAST ON SUNDAY AS THE SMALL CYCLONE MOVES AROUND THE WESTERN PERIPHERY OF A SUBTROPICAL RIDGE THAT EXTENDS EAST-WEST ALONG 28N LATITUDE. BY 24 HOURS...A SHORTWAVE TROUGH CURRENTLY ALONG THE U.S. MID-ATLANTIC COAST IS EXPECTED TO CAPTURE EMILY AND ACCELERATE IT TO THE EAST-NORTHEAST WITHIN THE MID-LATITUDE WESTERLIES. EMILY IS FORECAST TO MERGE WITH A FRONTAL SYSTEM AROUND THE 48-HOUR TIME PERIOD. THE FORECAST TRACK IS SIMILAR TO BUT A LITTLE SOUTH OF THE PREVIOUS ADVISORY TRACK...AND IS ALONG THE RIGHT SIDE OF THE NHC GUIDANCE ENVELOPE. AFTER LOOKING REASONABLY IMPRESSIVE EARLIER THIS AFTERNOON...EMILY IS NOW EXPERIENCING 10-15 OF NORTHEASTERLY SHEAR...WHICH HAS ELONGATED BOTH THE CONVECTIVE PATTERN AND THE SURFACE WIND FIELD IN A NORTHEAST-SOUTHWEST ORIENTATION. MODEST NORTHEAST TO EASTERLY SHEAR IS EXPECTED TO CONTINUE FOR THE NEXT 12-18 HOURS...WHICH SHOULD INHIBIT ANY SIGNIFICANT DEVELOPMENT. BY 24 HOURS... HOWEVER...THE VERTICAL SHEAR IS FORECAST TO RELAX...WHICH MAY ALLOW FOR SOME SLIGHT INTENSIFICATION TO OCCUR BEFORE WESTERLY WIND SHEAR BEGINS TO AFFECT THE CYCLONE AND INDUCES WEAKENING. THE EXACT TIMING OF MERGER WITH A WEAK FRONTAL SYSTEM THAT EXTENDS FROM THE CAROLINAS TO NEAR BERMUDA IS DIFFICULT TO ASSESS THIS TIME OF THE YEAR OVER SUCH WARM SSTS. ALTHOUGH DISSIPATION IS FORECAST TO OCCUR SHORTLY AFTER THE 48-HOUR TIME PERIOD...IT WOULD NOT BE OUT OF THE QUESTION FOR EMILY TO MAINTAIN ITS IDENTITY OUT TO 72 HOURS AS INDICATED BY THE SHIPS/LGEM INTENSITY MODELS. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE PREVIOUS ADVISORY AND IS A BLEND OF THE SHIPS/LGEM MODELS. ANOTHER RECONNAISSANCE FLIGHT IS SCHEDULED FOR SUNDAY AFTERNOON. FORECAST POSITIONS AND MAX WINDS INIT 07/0300Z 27.4N 78.2W 30 KT 35 MPH 12H 07/1200Z 29.2N 76.9W 35 KT 40 MPH 24H 08/0000Z 30.9N 74.0W 35 KT 40 MPH 36H 08/1200Z 32.5N 69.1W 35 KT 40 MPH 48H 09/0000Z 34.0N 62.0W 30 KT 35 MPH 72H 10/0000Z...DISSIPATED $$ FORECASTER STEWART