Show Selection: |
#110250 (Received by flhurricane at: 4:34 PM 11.Sep.2006) TCDAT1 HURRICANE FLORENCE DISCUSSION NUMBER 33 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062006 500 PM EDT MON SEP 11 2006 CLOUD TOPS HAVE BEEN WARMING DURING THE PAST FEW HOURS AND RADAR IMAGERY FROM BERMUDA INDICATES AN EYE THAT IS OPEN TO THE EAST. GIVEN THE STRONG WINDS REPORTED ACROSS BERMUDA...WE ARE RELUCTANT TO DECREASE THE WINDS AT THIS TIME. SOUTHWESTERLY SHEAR AND COOLER SSTS ARE EXPECTED TO IMPART A GRADUAL WEAKENING DURING THE NEXT 24 HOURS. AS FLORENCE BECOMES EXTRATROPICAL IN ABOUT 36 TO 48 HOURS... IT WILL LIKELY INTERACT WITH A SHORT WAVE IN THE WESTERLIES WHICH WILL PROBABLY KEEP THE EXTRATROPICAL CYCLONE LARGE AND VERY POWERFUL FOR SEVERAL MORE DAYS. THE INITIAL MOTION ESTIMATE IS 020/14. FLORENCE IS BEGINNING TO ACCELERATE NORTH-NORTHEASTWARD AHEAD OF A MID-LEVEL TROPOSPHERIC TROUGH OVER THE CANADIAN MARITIMES. DYNAMICAL TRACK MODEL GUIDANCE REMAINS IN FAIRLY GOOD AGREEMENT. HOWEVER...THE MODELS ARE NOW LEANING A LITTLE MORE TOWARD NEWFOUNDLAND IN ABOUT 48 HOURS BEFORE DEPICTING A HARD RIGHT TURN INTO THE NORTH ATLANTIC. THEREFORE... THE OFFICIAL FORECAST IS SHIFTED A LITTLE TO THE LEFT IN ABOUT 2 DAYS...BUT IS OTHERWISE SIMILAR TO THE PREVIOUS NHC TRACK. A TIGHT PRESSURE GRADIENT BETWEEN FLORENCE AND A STRONG HIGH CENTERED OVER SOUTHEASTERN CANADA IS PRODUCING BRISK NORTHEASTERLY WINDS ALONG THE EAST COAST OF THE UNITED STATES. THIS IS EXPECTED TO CAUSE VERY ROUGH AND DANGEROUS SURF CONDITIONS ALONG NEARLY THE ENTIRE EAST COAST OF NORTH AMERICA FOR THE NEXT SEVERAL DAYS. THE RADII OF 12-FT SEAS SHOWN IN THE FORECAST/ADVISORY DOES NOT FULLY ACCOUNT FOR THE HUGE AREA OF HIGH WAVES INDIRECTLY ASSOCIATED WITH THIS HURRICANE. EVEN THOUGH FLORENCE PASSED ABOUT 48 N MI WEST AND NORTHWEST OF BERMUDA...THEY WERE VERY CLOSE TO THE RADIUS OF MAXIMUM WINDS AND OBSERVATIONS INDICATE THAT THE ISLAND EXPERIENCE HURRICANE FORCE WINDS. THIS IS A GOOD REMINDER THAT A HURRICANE IS NOT JUST A POINT ON THE MAP...AND THAT DAMAGING WINDS CAN BE EXPERIENCED WELL AWAY FROM THE CENTER. FORECAST POSITIONS AND MAX WINDS INITIAL 11/2100Z 34.4N 64.8W 80 KT 12HR VT 12/0600Z 36.2N 63.8W 70 KT 24HR VT 12/1800Z 38.7N 61.9W 65 KT 36HR VT 13/0600Z 42.0N 58.5W 65 KT 48HR VT 13/1800Z 45.2N 54.8W 60 KT...EXTRATROPICAL 72HR VT 14/1800Z 49.0N 42.0W 55 KT...EXTRATROPICAL 96HR VT 15/1800Z 51.0N 25.0W 50 KT...EXTRATROPICAL 120HR VT 16/1800Z...ABSORBED $$ FORECASTER BROWN/PASCH |