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#377513 (Received by flhurricane at: 10:43 AM 20.Sep.2010) TCDAT2 TROPICAL STORM JULIA DISCUSSION NUMBER 34 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL122010 1100 AM AST MON SEP 20 2010 DEEP CONVECTION HAS BEEN SHEARED OFF TO THE EAST OF THE CENTER BY THE OUTFLOW OF HURRICANE IGOR...WITH THE COLDEST TOPS NOW A COUPLE OF HUNDRED MILES AWAY FROM THE CENTER. THE ASCAT PASS FROM 0046Z LAST NIGHT SHOWED THAT THE CIRCULATION WAS BECOMING ELONGATED EVEN THEN...AND VISIBLE IMAGERY THIS MORNING SHOWS THAT JULIA IS LOSING SOME DEFINITION AS IT BECOMES ENTANGLED WITH A FRONTAL TROUGH TO THE EAST OF THE CYCLONE. BASED ON THESE STRUCTURAL CHANGES...THIS WILL BE THE LAST ADVISORY. MORNING VISIBLE IMAGERY INDICATES THAT JULIA IS A LITTLE SOUTH OF THE PREVIOUS TRACK...AND IS MOVING AT 090/8. THE 00Z ECMWF HANDLED THE OVERNIGHT MOTION OF JULIA BEST...WITH THE OTHER GUIDANCE WELL TO THE LEFT AND SHOWING MORE OF AN INTERACTION WITH THE CIRCULATION OF IGOR. THE OFFICIAL FORECAST FOLLOWS THE ECMWF GUIDANCE WITH A FORECAST MOTION SOUTH OF THE PREVIOUS FORECAST. STRONG UPPER-LEVEL NORTHWESTERLY FLOW SHOULD KEEP THE SHEAR OVER JULIA ELEVATED...AND GIVEN THE MARGINAL SEA SURFACE TEMPERATURES... PREVENT THE SYSTEM FROM REDEVELOPING ORGANIZED DEEP CONVECTION. IF PRESENT TRENDS CONTINUE...THE CIRCULATION OF JULIA WILL BECOME ILL-DEFINED WITHIN A FRONTAL TROUGH OVER THE NEXT DAY OR SO. THAT SCENARIO IS REFLECTED IN THE OFFICIAL FORECAST...ALTHOUGH IT IS POSSIBLE THAT JULIA COULD REMAIN WELL-ENOUGH DEFINED TO LINGER AND MOVE EASTWARD AS A REMNANT LOW FOR SEVERAL DAYS...AS SHOWN BY THE ECMWF. FORECAST POSITIONS AND MAX WINDS INITIAL 20/1500Z 34.7N 46.4W 40 KT...POST-TROPICAL 12HR VT 21/0000Z 34.9N 45.3W 35 KT...POST-TROPICAL 24HR VT 21/1200Z 35.5N 43.0W 30 KT...POST-TROP/REMNT LOW 36HR VT 22/0000Z...DISSIPATED $$ FORECASTER FRANKLIN |