000 WTPZ44 KNHC 021455 TCDEP4 TROPICAL STORM DOUGLAS DISCUSSION NUMBER 3 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042008 800 AM PDT WED JUL 02 2008 A 1252 UTC SSMIS MICROWAVE IMAGE INDICATES THAT THE CENTER IS A LITTLE NORTHEAST OF THE PREVIOUS ESTIMATES. THE OVERALL CLOUD PATTERN HAS CONTINUED TO IMPROVE WITH A WELL-DEFINED BAND TO THE SOUTH AND SOUTHWEST OF THE ESTIMATED CENTER. THE LATEST DVORAK INTENSITY ESTIMATE FROM TAFB SUGGESTS THAT THE DEPRESSION HAS REACHED TROPICAL STORM STRENGTH AND THE INITIAL INTENSITY IS SET AT 35 KT. A SHIP LOCATED SOUTHWEST OF THE MAIN BAND OF THUNDERSTORM ACTIVITY REPORTED 27 KT AT 1200 UTC. ASSUMING THAT THE WINDS ARE STRONGER IN THE CONVECTION...THIS WOULD ALSO SUPPORT UPGRADING THE SYSTEM TO TROPICAL STORM STATUS. UNFORTUNATELY...QUIKSCAT HAS MISSED THE SYSTEM THIS MORNING. THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 315/7. DOUGLAS IS LOCATED TO THE SOUTH OF A MID-LEVEL RIDGE THAT EXTENDS FROM THE SOUTHWESTERN UNITED STATES INTO MEXICO. THE GLOBAL MODELS FORECAST A GENERAL NORTHWESTWARD MOTION DURING THE NEXT COUPLE OF DAYS WITH SOME DECREASE IN FORWARD SPEED. THE GFDL MODEL IS ON THE RIGHT SIDE OF THE MODEL ENVELOPE AND SHOWS A TRACK CLOSER TO THE BAJA PENINSULA. THIS MODEL HAS PERFORMED WELL IN THIS PORTION OF THE BASIN AND CANNOT BE DISCOUNTED AT THIS TIME. THE NEW NHC TRACK FORECAST HAS BEEN ADJUSTED A LITTLE NORTHWARD AND IS NEAR THE CENTER OF THE GUIDANCE. DOUGLAS IS EXPECTED TO REMAIN OVER GREATER THAN 26 DEGREE SSTS FOR THE NEXT 36 HOURS. HOWEVER...SOME EASTERLY SHEAR IS FORECAST WHICH SHOULD KEEP STRENGTHENING GRADUAL. THE OFFICIAL INTENSITY FORECAST IS A LITTLE ABOVE THE GUIDANCE AND INDICATES A PEAK INTENSITY OF 50 KT IN 24-36 HOURS. THEREAFTER...DOUGLAS WILL BE MOVING OVER COOLER WATERS WHICH SHOULD INDUCE STEADY WEAKENING AND THE FORECAST SHOWS THE CYCLONE DEGENERATING TO A REMNANT LOW LATE IN THE FORECAST PERIOD. GIVEN THE UNCERTAINTIES IN THE FORECAST TRACK...INTERESTS IN SOUTHERN BAJA SHOULD MONITOR THE PROGRESS OF DOUGLAS. FORECAST POSITIONS AND MAX WINDS INITIAL 02/1500Z 17.8N 107.8W 35 KT 12HR VT 03/0000Z 18.2N 108.1W 40 KT 24HR VT 03/1200Z 19.1N 108.9W 50 KT 36HR VT 04/0000Z 19.6N 109.9W 50 KT 48HR VT 04/1200Z 20.1N 110.9W 45 KT 72HR VT 05/1200Z 20.8N 112.3W 35 KT 96HR VT 06/1200Z 21.5N 113.5W 25 KT 120HR VT 07/1200Z 21.5N 115.0W 20 KT...REMNANT LOW $$ FORECASTER BROWN