000 WTPZ44 KNHC 131456 TCDEP4 TROPICAL STORM CARLOS DISCUSSION NUMBER 14 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042009 800 AM PDT MON JUL 13 2009 A 1045 UTC TRMM MICROWAVE PASS INDICATES THAT CARLOS HAS BEEN MOVING SOUTH OF DUE WEST AT 260/12 OVER THE PAST FEW HOURS AND IS A LITTLE FARTHER SOUTH THAN PREVIOUSLY ESTIMATED. THE SAME PASS IS ALSO SHOWING THAT THE CONVECTIVE BANDING MAY BE BECOMING A LITTLE MORE ORGANIZED AROUND THE CENTER. HOWEVER...THE SATELLITE INTENSITY ESTIMATES STILL SUPPORT AN INITIAL INTENSITY OF 45 KT. WHEREAS IT APPEARED THAT CARLOS WAS DETACHING FROM THE ITCZ A COUPLE OF DAYS AGO...SATELLITE IMAGERY NOW SUGGESTS THAT IT HAS BECOME RE-ATTACHED TO THE AXIS. THIS MIGHT BE CONTRIBUTING TO THE WEST TO WEST-SOUTHWESTERLY MOTION OVER THE PAST 12-24 HOURS. THE GUIDANCE ENVELOPE STILL SUGGESTS THAT CARLOS SHOULD GAIN SOME LATITUDE DURING THE NEXT 48 HOURS...BUT THE RECENT MOTION MAKES THIS SCENARIO UNCERTAIN. THE NEW OFFICIAL FORECAST IS SIMILAR TO THE PREVIOUS FORECAST EXCEPT THAT IT IS SHIFTED AS MUCH AS A DEGREE FARTHER SOUTH TO ACCOUNT FOR THE UPDATED INITIAL POSITION. CARLOS' INVOLVEMENT WITH THE ITCZ COMPLICATES THE INTENSITY FORECAST. IF THE CYCLONE CONTINUES TO MOVE WEST-SOUTHWESTWARD ALONG THE AXIS...RE-STRENGTHENING WOULD BE HIGHLY UNLIKELY. IN FACT...SOME OF THE MORE RELIABLE GLOBAL MODELS...PARTICULARLY THE GFS AND ECMWF...KEEP CARLOS EMBEDDED WITHIN THE ITCZ AND OPEN IT INTO A TROUGH VERY SOON. THE HWRF IS ALSO PESSIMISTIC AND ESSENTIALLY DISSIPATES THE CYCLONE IN A FEW DAYS. CONVERSELY...THE SHIPS/LGEM GUIDANCE SHOWS VERY LITTLE CHANGE IN INTENSITY OVER THE NEXT 5 DAYS WHILE THE GFDL RE-STRENGTHENS THE SYSTEM TO A HURRICANE. THE OFFICIAL INTENSITY FORECAST REMAINS UNCHANGED FROM THE PREVIOUS ADVISORY EXCEPT THAT IT BRINGS THE INTENSITY DOWN A LITTLE FASTER BY DAY 5 DUE TO INCREASING VERTICAL SHEAR. WHILE THE OFFICIAL WIND SPEED PROBABILITY PRODUCT INDICATES A 50% CHANCE THAT CARLOS WILL BE A DEPRESSION OR DISSIPATED BY DAY 5...I SUSPECT THE CHANCES ARE HIGHER THAN THAT. FORECAST POSITIONS AND MAX WINDS INITIAL 13/1500Z 9.6N 125.3W 45 KT 12HR VT 14/0000Z 9.6N 127.1W 50 KT 24HR VT 14/1200Z 9.9N 129.3W 50 KT 36HR VT 15/0000Z 10.2N 131.5W 55 KT 48HR VT 15/1200Z 10.5N 133.5W 55 KT 72HR VT 16/1200Z 11.0N 137.5W 55 KT 96HR VT 17/1200Z 11.5N 142.0W 50 KT 120HR VT 18/1200Z 11.5N 148.0W 40 KT $$ FORECASTER BERG