000 WTNT43 KNHC 160247 TCDAT3 TROPICAL STORM BILL DISCUSSION NUMBER 3 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032009 1100 PM AST SAT AUG 15 2009 SATELLITE IMAGES CONTINUE TO SHOW THAT BILL IS GRADUALLY BECOMING BETTER ORGANIZED WITH NUMEROUS CONVECTIVE BANDING FEATURES. HOWEVER...THE CYCLONE LACKS AN INNER CORE AND DEEP CONVECTION NEAR THE CENTER. INITIAL INTENSITY IS KEPT AT 35 KNOTS WHICH IS A BLEND OF THE DVORAK CLASSIFICATIONS AND QUIKSCAT DATA. WITH THE CONDUCIVE ENVIRONMENT AHEAD...BILL IS FORECAST TO BECOME A HURRICANE IN A COUPLE OF DAYS AND BECOME EVEN STRONGER THEREAFTER. THIS IS CONSISTENT WITH SHIPS AND BOTH THE GFDL/HWRF MODEL PAIR. BILL IS MOVING WESTWARD OR 270 DEGREES AT 14 KNOTS. THE CYCLONE IS WELL-EMBEDDED IN THE TROPICAL TRADE WINDS AND WILL CONTINUE ON THIS GENERAL TRACK WITH A GRADUAL TURN TO THE WEST-NORTHWEST. THE ECMWF WAS THE LEADER SHOWING A GRADUAL NORTHWARD TREND AHEAD OF A TROUGH OVER THE EASTERN UNITED STATES A FEW RUNS AGO. NOW...THE REST OF THE MODELS...WITH THE EXCEPTION OF THE UK MODEL...ARE FOLLOWING THE ECMWF TUNE...AND ALL TURN BILL MORE THE WEST-NORTHWEST AND NORTHWEST BY THE END OF THE FORECAST PERIOD. BASED ON THIS SHIFT IN THE GUIDANCE...THE OFFICIAL FORECAST WAS ALSO SHIFTED A LITTLE NORTHWARD AND IS IN THE MIDDLE OF THE TIGHTLY PACKED GUIDANCE ENVELOPE. FORECAST POSITIONS AND MAX WINDS INITIAL 16/0300Z 11.3N 36.6W 35 KT 12HR VT 16/1200Z 11.2N 38.7W 40 KT 24HR VT 17/0000Z 12.0N 41.5W 50 KT 36HR VT 17/1200Z 12.8N 44.0W 55 KT 48HR VT 18/0000Z 14.0N 47.0W 65 KT 72HR VT 19/0000Z 15.5N 52.5W 75 KT 96HR VT 20/0000Z 18.0N 58.5W 85 KT 120HR VT 21/0000Z 21.0N 64.0W 95 KT $$ FORECASTER AVILA