000 WTPZ45 KNHC 150834 TCDEP5 TROPICAL DEPRESSION FIFTEEN-E DISCUSSION NUMBER 2 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP152007 200 AM PDT MON OCT 15 2007 THE SATELLITE PRESENTATION OF THE TROPICAL CYCLONE IS ESSENTIALLY A BLOB OF COLD CLOUD TOPS...WITH NO EVIDENCE OF BANDING FEATURES IN THE DEEP CONVECTION. ALTHOUGH SOME OF THE VERY HIGH CIRRUS CLOUDS ARE RADIATING OUTWARD SLIGHTLY OVER THE EASTERN PART OF THE SYSTEM...MOST OF THE UPPER-LEVEL OUTFLOW IS CONFINED TO THE WESTERN SEMICIRCLE. DVORAK INTENSITY ESTIMATES ARE AT MARGINAL TROPICAL STORM STRENGTH BUT THE CURRENT INTENSITY ESTIMATE IS HIGHLY DEPENDENT ON HOW CLOSE THE LOW-LEVEL CENTER IS TO THE EDGE OF THE DEEP CONVECTION. SINCE THE CENTER POSITION CANNOT BE DETERMINED WITH MUCH CERTAINTY ON THE INFRARED IMAGES...I AM RELUCTANT TO UPGRADE THE SYSTEM TO A TROPICAL STORM AT THIS TIME. LATEST FIXES FROM TAFB AND SAB ARE SUBSTANTIALLY TO THE WEST OF THE PREVIOUS TRACK. FOR THE SAKE OF CONTINUITY...HOWEVER...THE TRACK IS SHIFTED ONLY SLIGHTLY TO THE LEFT OF THE PREVIOUS ADVISORY. INITIAL MOTION IS GUESSED TO BE 330/2. A VERY WEAK STEERING PATTERN PREVAILS IN THE VICINITY OF THE TROPICAL CYCLONE. THERE IS A BREAK IN THE SUBTROPICAL RIDGE TO THE NORTH OF THE DEPRESSION DUE TO A MID-LEVEL TROUGH APPROACHING THE BAJA PENINSULA. AFTER THE TROUGH PASSES TO THE EAST OF BAJA IN A COUPLE OF DAYS...SOME WEAK RIDGING IS LIKELY TO BUILD TO THE NORTH OF THE TROPICAL CYCLONE. DURING THE NEXT DAY OR SO...THE TROPICAL CYCLONE COULD DEVELOP SOME EASTWARD COMPONENT OF MOTION AS IT IS PULLED PARTIALLY INTO A BROAD LOW- TO MID-LEVEL CYCLONIC GYRE TO ITS EAST. HOWEVER A SLOW NORTH-NORTHWESTWARD MOTION IS EXPECTED LATER IN THE FORECAST PERIOD. THE OFFICIAL TRACK FORECAST IS IN BEST AGREEMENT WITH THE GFDL MODEL SOLUTION. MODERATE EASTERLY SHEAR IS CONTINUING TO AFFECT THE CYCLONE. GLOBAL MODELS SUGGEST THAT THERE MAY BE SOME ABATEMENT OF THE SHEAR OVER THE NEXT DAY OR TWO WHICH WOULD ALLOW FOR SOME STRENGTHENING. THE OFFICIAL INTENSITY FORECAST IS THE SAME AS IN THE PREVIOUS ADVISORY PACKAGE AND IS QUITE CLOSE TO THE INTENSITY MODEL CONSENSUS...ICON. FORECAST POSITIONS AND MAX WINDS INITIAL 15/0900Z 15.3N 108.9W 30 KT 12HR VT 15/1800Z 15.4N 109.0W 35 KT 24HR VT 16/0600Z 15.6N 108.9W 40 KT 36HR VT 16/1800Z 15.8N 108.8W 45 KT 48HR VT 17/0600Z 16.2N 109.0W 50 KT 72HR VT 18/0600Z 16.8N 109.3W 50 KT 96HR VT 19/0600Z 17.5N 110.0W 50 KT 120HR VT 20/0600Z 18.5N 111.0W 45 KT $$ FORECASTER PASCH