Show Selection: |
#386360 (Received by flhurricane at: 10:40 PM 29.Oct.2010) TCDAT5 TROPICAL STORM SHARY DISCUSSION NUMBER 5 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL202010 1100 PM AST FRI OCT 29 2010 DEEP CONVECTION HAS PERSISTED THIS EVENING AND HAS EXPANDED A BIT OVER THE SOUTHEAST THROUGH NORTHEAST PORTION OF THE CYCLONE. EARLIER REPORTS FROM AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT WITHIN THIS PARTICULAR AREA WERE 73 KT AT FLIGHT LEVEL...AND 60 KT BASED ON AN SFMR WIND ESTIMATION. CONSEQUENTLY...THE INITIAL INTENSITY IS HELD AT 60 KT FOR THIS ADVISORY. SHARY IS MOVING WITHIN A REGION OF INCREASING SOUTHERLY SHEAR...NOW 20-30 KT...AND IS FORECAST TO INCREASE FURTHER THROUGH THE PERIOD. THE SHEAR ALONG WITH COOLER SEA SURFACE TEMPERATURES SHOULD INDUCE A WEAKENING TREND DURING THE NEXT 24 HOURS. SATELLITE IMAGERY INDICATES THAT A BAROCLINIC SYSTEM IS RAPIDLY APPROACHING BERMUDA...AND INTERACTION WITH SHARY SHOULD BEGIN LATER TONIGHT. THE FSU CYCLONE PHASE EVOLUTION DIAGRAMS FOR THE GFS/UKMET/CMC UNANIMOUSLY AGREE THAT SHARY WILL COMPLETE THE TRANSITION TO AN EXTRATROPICAL LOW WITHIN 24 HOURS...AND THIS IS INDICATED IN THE OFFICIAL FORECAST. THE INITIAL MOTION IS ESTIMATED TO BE NORTHEASTWARD...050/18. THIS GENERAL MOTION IS EXPECTED TO CONTINUE WITHIN THE DEEP SOUTHWESTERLY TROPOSPHERIC FLOW DURING THE NEXT 24 HOURS AS THE SYSTEM MAKES ITS TRANSITION TO A NON-TROPICAL LOW. THE LIFE EXPECTANCY OF POST-TROPICAL SHARY SHOULD BE SHORT...AS ALL OF THE LARGE-SCALE MODELS SUGGEST THAT THE CYCLONE WILL BECOME ABSORBED BY THE FRONTAL ZONE IN 36 HOURS. THE OFFICIAL FORECAST IS BASED ON A BLEND OF THE GFS...ECMWF...AND THE UKMET...AND IS ADJUSTED TO THE RIGHT OF THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 30/0300Z 31.9N 63.3W 60 KT 12HR VT 30/1200Z 34.5N 59.0W 50 KT 24HR VT 31/0000Z 38.2N 51.7W 45 KT...POST-TROP/EXTRATROP 36HR VT 31/1200Z...ABSORBED BY FRONT $$ FORECASTER ROBERTS/BROWN |