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#98848 (Received by flhurricane at: 11:03 PM 20.Jul.2006) TCDAT2 TROPICAL STORM BERYL DISCUSSION NUMBER 11 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022006 1100 PM EDT THU JUL 20 2006 RECENT SATELLITE IMAGERY SHOWS THAT CONVECTION HAS BEEN DIMINISHING AND SHIFTING TO THE NORTHEASTERN PORTION OF THE STORM. DESPITE BERYL'S RAGGED APPEARANCE... THE AIRCRAFT MEASURED 54 KT FROM 850 MB AT 2314 UTC... WHICH EQUATES TO ROUGHLY 45 KT AT THE SURFACE USING STANDARD REDUCTION FACTORS. LOW-LEVEL WINDS FROM A DROPSONDE VERY NEAR THAT LOCATION IN THE MAXIMUM WIND BAND ALSO SUPPORTED SURFACE WINDS OF ABOUT 45 KT... A LITTLE SURPRISING GIVEN THE LACK OF DEEP CONVECTION IN THAT AREA. THE INITIAL INTENSITY WILL REMAIN 45 KT FOR THIS ADVISORY. SLOW WEAKENING SHOULD CONTINUE AS THE CYCLONE MOVES OVER COLD WATERS LESS THAN 22C AND GENERALLY INCREASING SHEAR. EXTRATROPICAL TRANSITION SHOULD OCCUR WITHIN A DAY OR SO DUE TO THE ABOVE FACTORS. BERYL IS MOVING 040/11...ABOUT THE SAME AS BEFORE. ON THIS HEADING BERYL WILL BE PASSING VERY NEAR NANTUCKET AND SOUTHEASTERN CAPE COD IN THE EARLY MORNING HOURS. INCREASING SOUTHWESTERLY FLOW AHEAD OF A MIDDLE TO UPPER-LEVEL TROUGH MOVING THROUGH THE GREAT LAKES SHOULD CAUSE THE CYCLONE TO ACCELERATE NORTHEASTWARD AFTER IT DEPARTS SOUTHEASTERN MASSACHUSETTS. MODEL GUIDANCE IS WELL-CLUSTERED ON THE NORTHEASTWARD TRACK SOLUTION AND LITTLE CHANGE WAS MADE TO THE FORECAST TRACK. WIND RADII BEYOND 12 HOURS HAVE BEEN ADJUSTED IN ACCORDANCE WITH GLOBAL MODELS SHOWING MOST OF THE WIND ON THE SOUTHEAST SIDE OF THE EXTRATROPICAL REMNANT OF BERYL. FORECAST POSITIONS AND MAX WINDS INITIAL 21/0300Z 40.2N 71.3W 45 KT 12HR VT 21/1200Z 41.9N 69.0W 40 KT 24HR VT 22/0000Z 44.8N 64.3W 35 KT...EXTRATROPICAL 36HR VT 22/1200Z 47.5N 58.5W 35 KT...EXTRATROPICAL 48HR VT 23/0000Z...ABSORBED |