Show Selection: |
#213296 (Received by flhurricane at: 4:41 PM 03.Sep.2008) TCDAT5 TROPICAL STORM JOSEPHINE DISCUSSION NUMBER 7 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL102008 500 PM EDT WED SEP 03 2008 STRONG VERTICAL SHEAR AND DRY AIR HAVE REALLY WORKED A NUMBER ON JOSEPHINE DURING THE LAST SEVERAL HOURS. AFTER LOOKING RATHER IMPRESSIVE EARLY THIS MORNING...THE SATELLITE PRESENTATION HAS SINCE RAPIDLY DEGRADED. CLOUD TOPS HAVE WARMED AND THERE IS NOW A NOTICEABLE LACK OF ORGANIZATION. THE INITIAL INTENSITY IS LOWERED TO 50 KT BASED ON A BLEND OF THE VARIOUS SATELLITE ESTIMATES BUT THIS COULD BE A BIT GENEROUS GIVEN JOSEPHINE'S CURRENT APPEARANCE. IN TERMS OF THE INTENSITY FORECAST...THE ENVIRONMENT GETS MORE HOSTILE FROM HERE. MOST OF THE GLOBAL MODELS INDICATE THAT JOSEPHINE WILL CONTINUE TO ENCOUNTER STRONG VERTICAL SHEAR AND SOME MODELS EVEN SUGGEST THE SHEAR WILL INCREASE. ADDITIONALLY...SSTS ALONG THE FORECAST TRACK GRADUALLY DECREASE THROUGH ABOUT 3 DAYS. THE ENVIRONMENT DOES BECOME A LITTLE MORE CONDUCIVE FOR STRENGTHENING AT DAYS 4 AND 5. HOWEVER...IT IS UNCLEAR WHAT WILL BE LEFT OF JOSEPHINE BY THAT TIME. THE NEW OFFICIAL INTENSITY FORECAST IS A LITTLE LOWER THAN THE PREVIOUS ADVISORY AND CALLS FOR GRADUAL WEAKENING. WITH JOSEPHINE'S FUTURE VERTICAL DEPTH NOW IN QUESTION...THE STEERING IS A LITTLE LESS CERTAIN. IF THE CYCLONE CANNOT GENERATE NEW CONVECTION...IT COULD BE STEERED MORE BY THE SHALLOW CURRENTS AND MOVE WESTWARD OR WEST-NORTHWESTWARD AS SHOWN BY THE GFS. CONVERSELY...IF THE CYCLONE CAN REGENERATE CONVECTION AND REMAIN A DEEP SYSTEM...IT WOULD TEND TO MOVE NORTHWESTWARD AS SHOWN BY THE NOGAPS AND GFDL MODELS. IT IS ALSO POSSIBLE THAT THE CYCLONE COULD HAVE INTERMITTENT BURSTS OF CONVECTION RESULTING IN A STAIR-STEPPED TRACK. GIVEN THE CURRENT LACK OF ORGANIZATION AND ANTICIPATED STRONG SHEAR...THE OFFICIAL FORECAST LEANS TOWARD THE GFS RESULTING IN A SOUTHWARD SHIFT AND SLOWER FORWARD SPEED. FORECAST POSITIONS AND MAX WINDS INITIAL 03/2100Z 13.8N 29.9W 50 KT 12HR VT 04/0600Z 14.0N 31.8W 50 KT 24HR VT 04/1800Z 14.6N 34.1W 50 KT 36HR VT 05/0600Z 15.2N 36.5W 45 KT 48HR VT 05/1800Z 15.9N 38.8W 40 KT 72HR VT 06/1800Z 17.5N 43.5W 35 KT 96HR VT 07/1800Z 19.0N 48.0W 30 KT 120HR VT 08/1800Z 21.5N 52.5W 30 KT $$ FORECASTER RHOME |