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#98212 (Received by flhurricane at: 5:03 PM 18.Jul.2006) TCDAT2 TROPICAL DEPRESSION TWO DISCUSSION NUMBER 2 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022006 500 PM EDT TUE JUL 18 2006 RECONNAISSANCE DATA AND SATELLITE IMAGERY INDICATE THE DEPRESSION HAS CONTINUED TO BECOME BETTER ORGANIZED. RECENT DATA FROM THE AIRCRAFT THAT CAME IN AFTER SOME OF THE FORECAST PRODUCTS WERE ISSUED INDICATE 1000 FT FLIGHT-LEVEL WINDS OF 46 KT IN THE SOUTHEASTERN QUADRANT AND A PRESSURE OF 1007 MB. THIS CORRESPONDS TO AT LEAST 35 KT SURFACE WINDS...AND A TROPICAL CYCLONE UPDATE... OR TCU PRODUCT... WILL ISSUED SHORTLY INDICATING THAT THE CYCLONE IS NOW TROPICAL STORM BERYL. THE INITIAL MOTION ESTIMATE IS 360/05. THE GLOBAL MODELS AT 12Z AGAIN DID NOT INITIALIZE THE CYCLONE VERY WELL AND...AS A RESULT ...GRADUALLY SHEAR OUT A VERY WEAK SYSTEM NORTHWARD THROUGH 36-48 HOURS...AND THEN TURN GRADUALLY TURN IT NORTHEASTWARD. UNTIL THE MODELS SHOW THAT THEY HAVE A BETTER HANDLE ON THE INITIAL STATE OF THIS SYSTEM...I AM LEANING MORE TOWARD THE ECMWF...GFDL...AND THE BAM MODELS ON THE CYCLONE MAKING A SLIGHT S-BEND IN THE FORECAST TRACK THROUGH 48-72 HOURS. THIS SCENARIO IS SUPPORTED BY ALL THE MODELS WHICH INDICATE A SHORTWAVE TROUGH CURRENTLY OVER THE GREAT LAKES DIGGING EAST-SOUTHEASTWARD AND ERODING THE EASTERN PORTION OF THE SUBTROPICAL RIDGE ALONG THE MID-ATLANTIC STATES. THE MODELS ALSO AGREE THAT THE SUBTROPICAL RIDGE TO THE EAST OF THE CYCLONE WILL BUILD WESTWARD SLIGHTLY...WHICH APPEARS TO BE ONGOING RIGHT NOW BASED ON TRENDS NOTED IN WATER VAPOR IMAGERY. THE COMBINATION OF MID-LEVEL HEIGHT FALLS TO THE WEST AND HEIGHT RISES TO THE EAST SHOULD IS EXPECTED TO NUDGE THE CYCLONE ON A NORTH-NORTHWESTWARD TRACK THROUGH 48 HOURS. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS TRACK...BUT WAS SHIFTED SLIGHTLY TO THE EAST. UPPER-LEVEL OUTFLOW CONTINUES TO IMPROVE AND BECOME MORE SYMMETRICAL. THE SHIPS MODEL INDICATES THE VERTICAL SHEAR IS FORECAST TO BE ONLY 1 KT IN 24 HOURS...WHICH WOULD FAVOR SIGNIFICANT STRENGTHENING IN MOST CASES. ALTHOUGH SSTS APPEAR TO BE WARMER THAN WHAT THE SHIPS MODEL IS USING...DRY AIR ENTRAINMENT IN THE WESTERN SEMICIRCLE MAY MODULATE THE NORMAL INTENSIFICATION TREND FOR A SYSTEM LIKE THIS. THE SHIPS MODEL NOW BRINGS THE CYCLONE UP TO 50 KT IN 36 HOURS...AND THE OFFICIAL INTENSITY FORECAST REMAINS SLIGHTLY HIGHER. FORECAST POSITIONS AND MAX WINDS INITIAL 18/2100Z 33.3N 73.3W 30 KT 12HR VT 19/0600Z 33.7N 73.7W 40 KT 24HR VT 19/1800Z 34.4N 74.2W 45 KT 36HR VT 20/0600Z 35.2N 74.6W 50 KT 48HR VT 20/1800Z 36.0N 74.6W 55 KT 72HR VT 21/1800Z 37.4N 73.4W 55 KT 96HR VT 22/1800Z 39.5N 68.5W 50 KT 120HR VT 23/1800Z 42.5N 60.0W 40 KT...BECOMING EXTRATROPICAL |