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#7081 (Received by flhurricane at: 5:04 AM 02.Sep.2004) TCDAT1 HURRICANE FRANCES DISCUSSION NUMBER 34 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 AM EDT THU SEP 02 2004 AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT MONITORING FRANCES REPORTS A CENTRAL PRESSURE OF 936 MB AND MAXIMUM FLIGHT-LEVEL WINDS OF 138 KT AT 700 MB. A DROPSONDE IN THE NORTHEASTERN EYEWALL REPORTED WINDS INDICATING SURFACE WINDS NEAR 125 KT...AND THAT IS THE INITIAL INTENSITY FOR THIS ADVISORY. THIS IS IN GOOD AGREEMENT WITH 127 KT SATELLITE INTENSITY ESTIMATES FROM TAFB...SAB...AND AFWA. SATELLITE IMAGERY INDICATES COOLING OF THE CLOUD TOPS SINCE 06Z...ALTHOUGH AT THE MOMENT THIS CONVECTION IS RATHER ASYMMETRIC. THE INITIAL MOTION IS 290/11. FRANCES CONTINUES ON THE SOUTHWEST SIDE OF THE SUBTROPICAL RIDGE...A FEATURE THAT THE LARGE-SCALE MODELS ARE HAVING A PROBLEM FORECASTING THE EVOLUTION OF. THE SYNOPTIC SURVEILLANCE MISSION YESTERDAY SEEMS TO HAVE HAD LITTLE EFFECT ON THE MODELS...AS THE GFS AND GFDL STILL WANT TO TURN FRANCES MORE NORTHWARD....WHILE THE NOGAPS AND UKMET STILL FORECAST A WEST-NORTHWESTWARD MOTION ACROSS FLORIDA INTO THE GULF OF MEXICO. GIVEN THIS LACK OF CHANGE...THE ONLY CHANGE IN THE FORECAST TRACK DURING THE FIRST 72 HR IS BASED ON THE INITIAL POSITION AND CURRENT MOTION...WITH THIS PART OF THE TRACK IN BEST AGREEMENT WITH THE NOGAPS. AFTER 72 HR...THE TRACK IS SHIFTED WESTWARD TOWARD THE UKMET AND NOGAPS FORECASTS. THE FORECAST TRACK CALLS FOR LANDFALL IN SOUTHEAST OR EAST CENTRAL FLORIDA IN JUST OVER 48 HR. HOWEVER...PEOPLE SHOULD NOT FOCUS TOO CLOSELY ON THE EXACT TRACK... AS SMALL CHANGES IN DIRECTION COULD MAKE A SIGNIFICANT DIFFERENCE IN THE LANDFALL LOCATION. FRANCES CONTINUES TO SHOW IMPRESSIVE OUTFLOW...ALTHOUGH IT MAY BE DECREASING A LITTLE IN THE NORTHWESTERN QUADRANT. THE INTENSITY OF FRANCES CONTINUES TO BE CONTROLLED BY CONCENTRIC EYEWALL CYCLES. SINCE THESE ARE DIFFICULT TO FORECAST...THE INTENSITY FORECAST WILL CALL FOR 125 KT INTENSITY UNTIL LANDFALL. GIVEN THE CURRENT CLOUD TOP COOLING...FRANCES COULD REACH 130-135 KT INTENSITY ON THE UP SIDE OF THE CURRENT CYCLE. THE SOUTHWARD SHIFT IN THE FORECAST TRACK REQUIRES THE HURRICANE WATCH TO BE EXTENDED SOUTHWARD INTO THE UPPER FLORIDA KEYS. A HURRICANE WARNING IS NOT BEING ISSUED FOR SOUTHEASTERN FLORIDA AT THIS TIME AS THE 24 HR FORECAST KEEPS THE TROPICAL STORM WINDS OFFSHORE. HOWEVER...HURRICANE WARNINGS ARE LIKELY ON THE NEXT ADVISORY. FORECASTER BEVEN FORECAST POSITIONS AND MAX WINDS INITIAL 02/0900Z 22.9N 73.0W 125 KT 12HR VT 02/1800Z 23.6N 74.4W 125 KT 24HR VT 03/0600Z 24.6N 76.3W 125 KT 36HR VT 03/1800Z 25.6N 78.0W 125 KT 48HR VT 04/0600Z 26.6N 79.5W 125 KT 72HR VT 05/0600Z 28.0N 81.5W 95 KT...INLAND 96HR VT 06/0600Z 30.5N 84.0W 35 KT...INLAND 120HR VT 07/0600Z 33.5N 85.5W 25 KT...INLAND |