055 
 WTNT43 KNHC 290830
 TCDAT3
 TROPICAL STORM LISA DISCUSSION NUMBER  40
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 5 AM EDT WED SEP 29 2004
  
 A REPORT AT 6Z OF 34 KT FROM SHIP FQFL...ABOUT 175 NM NORTH-
 NORTHEAST OF THE CENTER OF LISA...GIVES ADDITIONAL SUPPORT TO SOME
 OF THE STRONGER WINDS IN THE EARLIER QUIKSCAT PASS AT 21Z...AND
 SUGGESTS THAT LISA HAD WINDS OF ABOUT 60 KT AT THAT TIME.  THE
 INITIAL INTENSITY IS INCREASED TO 60 KT ON THIS BASIS.  ALTHOUGH THE
 SYSTEM REMAINS SHEARED WITH A SHARPLY ELONGATED LOW-LEVEL
 CIRCULATION...DEEP CONVECTION IS NOW INCREASING NORTH...RATHER THAN
 NORTHEAST OF THE CENTER AND THE UPPER-LEVEL CIRRUS IS BEGINNING TO
 PUSH OUTWARD IN THE NORTHWEST QUADRANT.  THIS IS CONSISTENT WITH
 THE FORECAST CUTOFF OF AN UPPER-LEVEL LOW TO THE SOUTHWEST OF
 LISA...WHICH SHOULD ACT TO REDUCE THE SHEAR AND ALLOW LISA TO
 BECOME A HURRICANE OVER THE NEXT 24 HOURS BEFORE THE SYSTEM MOVES
 OVER COOLER WATERS.
  
 THE INITIAL MOTION ESTIMATE IS 010/11.  A TURN TO THE
 NORTH-NORTHWEST AROUND THE UPPER CUTOFF LOW IS EXPECTED DURING THE
 NEXT 24 HOURS...BEFORE LISA IS RELEASED FROM THE LOW AND ENCOUNTERS
 SOUTHWESTERLIES AHEAD OF THE REMNANTS OF HURRICANE JEANNE.  SOME
 GUIDANCE SUGGESTS THAT AS LISA WEAKENS OVER COOLER WATERS IT COULD
 MERGE WITH THE EXTRATROPICAL REMNANTS OF JEANNE...BUT I WILL CARRY
 POSITIONS OUT TO 120 HOURS IN CASE THE MERGER DOES NOT OCCUR.  NONE
 OF THE TRACK GUIDANCE HAS SHOWN THE EAST OF NORTH MOTION OBSERVED
 OVER THE PAST FEW HOURS...AND SO MY TRACK IS A LITTLE TO THE RIGHT
 OF THE GUIDANCE ENVELOPE FOR THE FIRST 24 HOURS OR SO.  AFTER
 THAT...THE OFFICIAL FORECAST IS JUST SLIGHTLY EAST OF THE PREVIOUS
 TRACK AND IS CLOSE TO THE DYNAMICAL MODEL CONSENSUS.  IT IS PERHAPS
 WORTH NOTING THAT THE GFDL HAS A TRACK A COUPLE HUNDRED MILES TO
 THE WEST OF MINE AND KEEPS LISA STRONGER LONGER.
 
 FORECASTER FRANKLIN
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      29/0900Z 28.0N  46.1W    60 KT
  12HR VT     29/1800Z 29.5N  46.2W    60 KT
  24HR VT     30/0600Z 31.3N  47.0W    65 KT
  36HR VT     30/1800Z 33.0N  48.0W    65 KT
  48HR VT     01/0600Z 35.0N  48.5W    60 KT
  72HR VT     02/0600Z 38.0N  46.5W    55 KT
  96HR VT     03/0600Z 42.0N  40.0W    50 KT...EXTRATROPICAL
 120HR VT     04/0600Z 43.5N  30.0W    45 KT...EXTRATROPICAL
  
  
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