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| #59304 (Received by flhurricane at: 4:17 PM 30.Nov.2005) TCDAT4 TROPICAL STORM EPSILON DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 4 PM EST WED NOV 30 2005 WHILE THE DEPTH OF THE CENTRAL CONVECTION HAS DECREASED AND CLOUD TOPS HAVE WARMED... THE OVERALL INNER AND OUTER CONVECTIVE PATTERNS HAVE INCREASED SIGNIFICANTLY...INCLUDING THE DEVELOPMENT OF A RAGGED 30 NMI DIAMETER EYE. SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB ARE 45 KT... AND 35 KT FROM AFWA... RESPECTIVELY. THE LOWER INTENSITY ESTIMATES ARE MAINLY DUE TO THE WARM CLOUD TOPS THAT ARE NOT ALLOWING FOR SOLID BANDING FEATURES ACCORDING TO THE DVORAK RULES... WHICH IS TYPICAL FOR SHALLOW TROPICAL CYCLONES LIKE EPSILON. HOWEVER... A 30/1008Z UW-CIMSS AMSU ESTIMATE OF 991 MB... THE IMPROVED CONVECTIVE STRUCTURE... AND THE EYE FEATURE ARE THE BASIS FOR INCREASING THE INITIAL INTENSITY TO 60 KT. THE MOTION ESTIMATE IS 180/06. THE MODELS HAVE ALL INDICATED THAT EPSILON WOULD MOVE WEST AND THEN NORTH BEFORE TURNING NORTHEASTWARD ...BUT THE CYCLONE HAS INSTEAD MOVED SOUTHWEST AND NOW SOUTHWARD. IT APPEARS THAT THE STRONG WRAPAROUND SURFACE TO MID-LEVEL RIDGE TO THE NORTH AND WEST OF EPSILON SHOULD FORCE THE CYCLONE TO MAKE A SMALL CLOCKWISE LOOP BEFORE EVENTUALLY TURNING NORTHEASTWARD BY 36 HOURS. THE MODELS ARE STILL IN GOOD AGREEMENT ON THE STEERING FLOW BECOMING WESTERLY AHEAD OF A DEEP LAYER TROUGH THAT IS FORECAST TO MOVE OFF THE U.S. EAST COAST BY 48 HOURS. THE OFFICIAL TRACK HAS BEEN SHIFTED SOUTHWARD OR TO THE RIGHT OF THE PREVIOUS TRACK TO ACCOUNT FOR THE MORE SOUTHERLY INITIAL POSITION... AND IS A LITTLE NORTH OF THE NHC MODEL CONSENSUS. HOWEVER... IF EPSILON KEEPS MOVING SOUTHWARD... SUBSEQUENT FORECAST TRACKS MAY HAVE TO BE SHIFTED MORE TO THE SOUTH... WHICH COULD RESULT IN EPSILON PASSING MUCH CLOSER TO THE AZORES ISLANDS IN 120 HOURS AND BEYOND. THE SOUTHWARD MOTION HAS RESULTED IN EPSILON MOVING OVER WARMER WATER... AS INDICATED BY NEARBY BUOY REPORTS OF 76-77F SSTS. CIRRUS CLOUD MOTIONS ALSO INDICATE A WELL-DEFINED UPPER-LEVEL ANTICYCLONE HAS DEVELOPED OVER THE CENTER. JUST A MODEST INCREASE IN CONVECTION IS NEEDED TO MAKE EPSILON A HURRICANE. THE CYCLONE IS EXPECTED TO BE OVER THE WARMEST WATER AND IN THE LOWEST SHEAR CONDITIONS FOR THE NEXT 6 TO 12 HOURS... AFTER WHICH INCREASING WESTERLY VERTICAL SHEAR AND DECREASING SSTS SHOULD INDUCE SLOW BUT STEADY WEAKENING. HOWEVER... EPSILON IS FORECAST REMAIN A SIGNIFICANT EXTRATROPICAL LOW PRESSURE SYSTEM DUE TO INCREASING BAROCLINIC EFFECTS. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 30/2100Z 29.8N 54.2W 60 KT 12HR VT 01/0600Z 30.5N 54.1W 60 KT 24HR VT 01/1800Z 31.1N 53.5W 55 KT 36HR VT 02/0600Z 32.1N 51.8W 55 KT 48HR VT 02/1800Z 33.2N 50.0W 50 KT...BECOMING EXTRATROPICAL 72HR VT 03/1800Z 35.0N 46.0W 50 KT...EXTRATROPICAL 96HR VT 04/1800Z 37.0N 41.0W 45 KT...EXTRATROPICAL 120HR VT 05/1800Z 39.0N 36.0W 40 KT...EXTRATROPICAL |
