000 WTPZ41 KNHC 120520 TCDEP1 TROPICAL DEPRESSION SIX-E SPECIAL DISCUSSION NUMBER 1 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP062008 1000 PM PDT FRI JUL 11 2008 CONVENTIONAL SATELLITE IMAGERY AND A NUMBER OF MICROWAVE OVERPASSES SUGGEST THAT THE AREA OF LOW PRESSURE SITUATED A FEW HUNDRED MILES SOUTH OF THE GULF OF TEHUANTEPEC HAS ACQUIRED SUFFICIENT ORGANIZED CONVECTION TO BE CLASSIFIED AS A TROPICAL DEPRESSION. A 0015Z QUIKSCAT PASS INDICATED 30 KT WINDS WITHING THE DEVELOPING SPIRAL BAND OVER THE EASTERN PORTION OF THE SYSTEM. ADDITIONALLY...DVORAK T-NUMBERS FROM TAFB AND SAB ARE 35 AND 30 KT RESPECTIVELY. THE INITIAL INTENSITY IS SET AT 30 KT FOR THIS ADVISORY. DYNAMICAL MODELS AND THE SHIPS SHOW THE EASTERLY SHEAR DECREASING AS THE CYCLONE TRAVERSES OVER WARM WATERS DURING THE NEXT 3 OF DAYS. THROUGH THE REMAINING PORTION OF THE FORECAST...THE SYSTEM IS EXPECTED TO MOVE OVER COOLER WATERS. THEREFORE...THE INTENSITY FORECAST CALLS FOR GRADUAL STRENGTHENING THROUGH THE 72 HOUR PERIOD...THEN HOLDING AT 60 KT THROUGH DAY 5. INITIAL MOTION IS ESTIMATED AT 300/14...WITHIN THE LOW TO MID LAYER FLOW SOUTH OF A RIDGE EXTENDING FROM THE GULF OF MEXICO WESTWARD OVER WESTERN MEXICO. LARGE-SCALE AND HURRICANE MODELS SUGGEST THAT THE RIDGE WILL BUILD FURTHER WEST OVER BAJA CALIFORNIA AS AN UPPER TROUGH OVER THE AREA WEAKENS AND DRIFTS NORTHWEST. THIS SYNOPTIC STEERING PATTERN SHOULD CAUSE THE DEPRESSION TO MOVE IN A GENERAL WEST-NORTHWESTWARD MOTION THROUGH THE ENTIRE FORECAST. THE FORECAST TRACK IS BASED ON A BLEND OF THE AVAILABLE DYNAMICAL MODELS AND THE GFS BAMM MID-LAYER MEAN TRAJECTORY MODEL. FORECAST POSITIONS AND MAX WINDS INITIAL 12/0500Z 12.3N 96.3W 30 KT 12HR VT 12/1200Z 13.1N 97.7W 35 KT 24HR VT 13/0000Z 14.0N 100.1W 40 KT 36HR VT 13/1200Z 14.8N 102.4W 45 KT 48HR VT 14/0000Z 15.6N 104.6W 50 KT 72HR VT 15/0000Z 17.0N 108.5W 60 KT 96HR VT 16/0000Z 18.0N 112.0W 60 KT 120HR VT 17/0000Z 18.5N 116.0W 60 KT $$ FORECASTER ROBERTS/KNABB