000 WTNT43 KNHC 260848 TCDAT3 TROPICAL DEPRESSION EIGHT DISCUSSION NUMBER 3 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082009 500 AM AST SAT SEP 26 2009 WHILE DEEP CONVECTION HAS INCREASED OVER THE PAST FEW HOURS... GEOSTATIONARY IMAGERY AND AN AMSR-E PASS FROM AROUND 0400 UTC SUGGEST THAT THE LOW-LEVEL CENTER IS LOCATED ON THE SOUTHWESTERN EDGE OF THE CONVECTION. THIS STRUCTURE IS LIKELY DUE TO THE 10-15 KT OF SOUTHWESTERLY SHEAR ANALYZED OVER THE CYCLONE BY UW-CIMSS AND THE SHIPS MODEL. DVORAK CI-NUMBERS WERE 1.5 AND 2.0 FROM SAB AND TAFB...RESPECTIVELY...AND THE INITIAL INTENSITY IS HELD AT 30 KT FOR THIS ADVISORY. CONDITIONS WILL BE ONLY MARGINALLY FAVORABLE FOR INTENSIFICATION OVER THE NEXT 2-3 DAYS. SSTS WILL BE 26-27C...AND THE SHIPS MODEL SHOWS THE SHEAR DECREASING BELOW 15 KT ONLY FOR A BRIEF PERIOD FROM 12 TO 24 HOURS. GIVEN THIS...THE OFFICIAL FORECAST HOLDS THE INTENSITY AT 30 KT THROUGH 24 HOURS AND THEN SHOWS A GRADUAL WEAKENING. HOWEVER...IT IS POSSIBLE THAT THE SYSTEM COULD BRIEFLY REACH TROPICAL STORM STATUS DURING THE NEXT DAY OR SO. THE INITIAL MOTION ESTIMATE IS 300/12...A LITTLE TO THE LEFT OF THE PREVIOUS ADVISORY. MOST OF THE TRACK GUIDANCE INDICATES THAT THE CYCLONE WILL ROUND THE WESTERN EDGE OF THE SUBTROPICAL RIDGE AND TURN TOWARD THE NORTHWEST OVER THE NEXT COUPLE OF DAYS. BEYOND THAT TIME...THE GFS...NOGAPS AND HWRF SHOW THE DEPRESSION OR ITS REMNANTS TURNING NORTHWARD AHEAD OF A FRONT...WHILE THE UKMET...ECMWF...AND THE MEDIUM BAM SUGGEST THAT WHAT IS LEFT OF THE CYCLONE WILL TURN WESTWARD. THE OFFICIAL FORECAST IS SOUTH OF THE PREVIOUS ONE FOR THE FIRST 24 HOURS DUE TO THE INITIAL MOTION...AND IS AN UPDATE OF THE PREVIOUS FORECAST BEYOND THAT TIME. AT DAY 3 ONLY A SLOW NORTHWESTWARD MOTION IS INDICATED DUE TO THE LARGE SPREAD IN THE GUIDANCE. FORECAST POSITIONS AND MAX WINDS INITIAL 26/0900Z 17.6N 33.8W 30 KT 12HR VT 26/1800Z 18.7N 35.3W 30 KT 24HR VT 27/0600Z 20.2N 36.9W 30 KT 36HR VT 27/1800Z 21.6N 38.1W 25 KT 48HR VT 28/0600Z 23.1N 39.3W 25 KT 72HR VT 29/0600Z 24.5N 40.5W 20 KT...REMNANT LOW 96HR VT 30/0600Z...DISSIPATED $$ FORECASTER BRENNAN