000 WTPZ42 KNHC 080236 TCDEP2 TROPICAL STORM ESTELLE DISCUSSION NUMBER 9 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072010 800 PM PDT SAT AUG 07 2010 THE LAST FEW GOES-E VISIBLE IMAGES AND A 2334Z AMSU MICROWAVE PASS INDICATED A SMALL OVAL CENTRAL DENSE OVERCAST DEVELOPING OVER THE CENTER OF ESTELLE. OUTER BANDS REMAIN IMPRESSIVE...PARTICULARLY OVER THE SOUTHWEST QUADRANT...AND THE SATELLITE INTENSITY ESTIMATES ARE 55 KT FROM BOTH TAFB AND SAB. THEREFORE...THE INITIAL INTENSITY IS BUMPED UP TO 55 KT. DURING THE NEXT 12-24 HOURS...THE GLOBAL AND SHIPS MODELS FORECAST AN ENVIRONMENT CONDUCIVE FOR SOME FURTHER STRENGTHENING...BEFORE THE SOUTHEAST TO EASTERLY SHEAR INCREASES AND A STABLE AIR MASS INDUCES GRADUAL WEAKENING. THIS SCENARIO SEEMS REASONABLE BASED ON THE IMPROVING CLOUD PATTERN AND DIFFLUENT OUTFLOW OVER THE WESTERN PORTION OF THE SYSTEM. THE OFFICIAL FORECAST FOLLOWS SUIT...IS BASED ON THE INTENSITY MODEL CONSENSUS...AND SHOWS WEAKENING TO A REMNANT LOW IN 96 HOURS. THE INITIAL MOTION IS SLIGHTLY TO THE RIGHT OF THE PREVIOUS TRACK AND A LITTLE SLOWER...280/7...AND IS SUPPORTED BY EARLIER TRMM...AMSU...AND SSMIS MICROWAVE OVERPASSES. LARGE-SCALE MODELS SUGGEST THAT THE WESTERN EXTENT OF THE SUBTROPICAL RIDGE TO THE NORTH OF ESTELLE WILL WEAKEN FURTHER IN RESPONSE TO A DEEPENING MAJOR SHORT WAVE TROUGH EXTENDING ALONG THE WEST COAST OF THE UNITED STATES. SUBSEQUENTLY...THE FORWARD MOTION OF THE CYCLONE SHOULD DECREASE FURTHER...POSSIBLY TO A WESTWARD DRIFT IN 3 DAYS. AFTERWARD...ALL OF THE DYNAMICAL MODELS SUGGEST THAT THE REMNANT LOW OF ESTELLE WILL COMMENCE A GENERAL DRIFT TOWARD THE SOUTHEAST AND EAST WITHIN AN INCREASING SOUTHWESTERLY MONSOONAL FLOW. THE NHC FORECAST IS BASED ON A MULTI-MODEL CONSENSUS AND CLOSELY FOLLOWS THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 08/0300Z 17.3N 109.4W 55 KT 12HR VT 08/1200Z 17.4N 110.2W 60 KT 24HR VT 09/0000Z 17.5N 111.3W 55 KT 36HR VT 09/1200Z 17.5N 112.3W 50 KT 48HR VT 10/0000Z 17.5N 113.1W 45 KT 72HR VT 11/0000Z 17.5N 114.0W 35 KT 96HR VT 12/0000Z 17.0N 114.5W 25 KT...POST-TROP/REMNT LOW 120HR VT 13/0000Z 16.0N 113.5W 20 KT...POST-TROP/REMNT LOW $$ FORECASTER ROBERTS/BEVEN