000 WTPZ41 KNHC 132037 TCDEP1 TROPICAL STORM KRISTY DISCUSSION NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112012 200 PM PDT THU SEP 13 2012 THE CENTER OF KRISTY HAS BECOME EXPOSED IN VISIBLE SATELLITE IMAGERY...WITH NORTH-NORTHWESTERLY SHEAR DISPLACING MOST OF THE DEEP CONVECTION TOWARD THE SOUTHEASTERN PART OF THE CIRCULATION. DVORAK CURRENT-INTENSITY ESTIMATES REMAIN 3.0 FROM TAFB AND SAB... SO THE ADVISORY INTENSITY IS HELD AT 45 KT. THE VERTICAL SHEAR IS EXPECTED TO DECREASE IN 24 TO 36 HOURS...ABOUT THE SAME TIME THE CENTER OF KRISTY CROSSES THE 26C SST ISOTHERM TOWARD COLDER WATER. IT IS UNLIKELY THAT KRISTY WILL STRENGTHEN WHILE THE SHEAR CONTINUES...AND THE NHC INTENSITY FORECAST SHOWS LITTLE CHANGE DURING THE NEXT 24 HOURS...FOLLOWED BY GRADUAL WEAKENING BEGINNING BY 48 HOURS. THE NHC FORECAST CLOSELY FOLLOWS A BLEND OF THE SHIPS AND LGEM MODELS. THE MOTION REMAINS 295/9 KT...AND THE SUBTROPICAL RIDGE SHOULD CONTINUE TO STEER KRISTY WEST-NORTHWESTWARD TO NORTHWESTWARD DURING THE NEXT 72 HOURS. THEREAFTER...A LARGE HIGH PRESSURE SYSTEM LOCATED OVER THE PACIFIC OFF THE CALIFORNIA COAST SHOULD STOP KRISTY FROM MOVING IN A WESTWARD DIRECTION...WITH THE REMNANT LOW LIKELY TURNING TOWARD THE NORTH AND NORTH-NORTHEAST. THERE IS CONSIDERABLE SPREAD IN THE TRACK GUIDANCE FROM 36 HOURS AND BEYOND...HIGHLIGHTED BY THE ECMWF AND GFDL TAKING A COURSE MUCH CLOSER TO THE BAJA COAST. THE NEW NHC TRACK FORECAST IS SHIFTED A LITTLE TO THE EAST OF THE PREVIOUS ONE...BUT ONLY AT 96 AND 120 HOURS WHEN KRISTY IS A REMNANT LOW. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 19.3N 110.2W 45 KT 50 MPH 12H 14/0600Z 19.8N 111.5W 45 KT 50 MPH 24H 14/1800Z 20.5N 113.1W 45 KT 50 MPH 36H 15/0600Z 21.8N 114.8W 40 KT 45 MPH 48H 15/1800Z 22.9N 116.5W 40 KT 45 MPH 72H 16/1800Z 24.5N 119.5W 30 KT 35 MPH 96H 17/1800Z 26.0N 120.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 18/1800Z 27.0N 119.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ FORECASTER BERG