641 
 WTNT41 KNHC 050828
 TCDAT1
 HURRICANE ALEX DISCUSSION NUMBER  20
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 5 AM EDT THU AUG 05 2004
  
 ALEX REMAINS WELL ORGANIZED THIS MORNING...WITH A WELL-DEFINED EYE
 SURROUNDED BY CONVECTIVE TOPS OF -65C TO -75C.  INDEED...THE CLOUD
 TOPS HAVE COOLED SOMEWHAT OVER THE PAST FEW HOURS.  SATELLITE
 INTENSITY ESTIMATES ARE 102 KT FROM ALL AGENCIES.  BASED ON
 THIS...THE MAXIMUM WINDS REMAIN 105 KT.  THE UPPER-LEVEL OUTFLOW IS
 FAIR IN THE NORTHEASTERN SEMICIRCLE AND POOR ELSEWHERE.
  
 THE INITIAL MOTION IS NOW 065/25.  ALEX IS WELL EMBEDDED IN THE
 WESTERLIES AND SHOULD CONTINUE AN ACCELERATING EAST-NORTHEASTWARD
 MOTION FOR 24 HR OR SO...FOLLOWED BY A GRADUAL TURN TOWARD THE
 EAST.  ALL TRACK GUIDANCE AGREES WITH THIS SCENARIO OUT TO 48-72
 HR...AND THE OFFICIAL FORECAST IS AN UPDATE OF THE PREVIOUS
 PACKAGE.
 
 THE CLOUD TOP COOLING CURRENTLY OCCURRING IS LIKELY TO BE THE LAST
 GASP FOR ALEX.  THE HURRICANE SHOULD MOVE NORTH OF THE GULF STREAM
 INTO MUCH COLDER SEA SURFACE TEMPERATURES DURING THE NEXT 12-18
 HOURS WHICH SHOULD CAUSE SIGNIFICANT WEAKENING.  ALEX WILL BEGIN
 EXTRATROPICAL TRANSITION AFTER 24 HR AND COMPLETE IT BY 48 HR. 
 WHILE DETAILS DIFFER...ALL LARGE-SCALE MODELS AGREE THAT
 EXTRATROPICAL ALEX WILL MERGE WITH EITHER ANOTHER EXTRATROPICAL LOW
 OR A COLD FRONT BY 72 HR AND LOSE ITS IDENTITY...AND THE INTENSITY
 FORECAST FOLLOWS THIS SCENARIO.
  
 FORECASTER BEVEN
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      05/0900Z 40.0N  61.5W   105 KT
  12HR VT     05/1800Z 42.0N  56.2W    95 KT
  24HR VT     06/0600Z 45.0N  46.5W    75 KT
  36HR VT     06/1800Z 47.0N  36.5W    60 KT...BECOMING EXTRATROPICAL
  48HR VT     07/0600Z 47.0N  26.5W    55 KT...EXTRATROPICAL
  72HR VT     08/0600Z...ABSORBED BY EXTRATROPICAL LOW
  
  
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