668 
 WTNT44 KNHC 161629
 TCDAT4
 HURRICANE IRENE DISCUSSION NUMBER  48...CORRECTED
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 11 AM EDT TUE AUG 16 2005
 ...CORRECTED TO REPLACE WORD EXTRACURRICULAR WITH EXTRATROPICAL...
 IRENE IS MAINTAINING INTENSITY AT THIS TIME...AS AN EYE HAS BEEN
 EVIDENT ON BOTH VISIBLE AND INFRARED IMAGES.  SSM/I IMAGERY ALSO
 SHOWS AN EYE...THAT IS CIRCULAR AND 20 N MI IN DIAMETER WITH A
 CLOSED WALL...ALBEIT A LITTLE WEAK OVER THE SOUTHERN SEMICIRCLE. 
 DVORAK CLASSIFICATIONS GIVE A T-NUMBER OF 4.5 WHICH SUPPORTS A
 CURRENT INTENSITY OF 75 KT.  EVEN THOUGH THE HURRICANE LOOKS QUITE
 HEALTHY AT THE MOMENT...ONLY A SMALL NORTHWARD COMPONENT OF MOTION
 WILL BRING THE SYSTEM INTO AN ENVIRONMENT OF MUCH HIGHER SHEAR...
 GREATER THAN 30 KNOTS.  THE OFFICIAL INTENSITY FORECAST... LIKE THE
 PREVIOUS ONE...SHOWS A WEAKENING TREND COMMENCING WITHIN 12-24
 HOURS AND THEN WEAKENS IRENE AT A SLIGHTLY FASTER RATE THAN
 PREDICTED BY THE SHIPS GUIDANCE.  GLOBAL MODELS INDICATE THAT IRENE
 WILL BEGIN TO INTERACT WITH A BAROCLINIC ZONE IN ABOUT 36 HOURS. 
 AFTER EXTRATROPICAL TRANSITION...THE SYSTEM WILL LIKELY MERGE
 WITH OR BECOME ABSORBED BY ANOTHER EXTRATROPICAL CYCLONE NEAR
 SOUTHERN GREENLAND.
 
 INITIAL MOTION IS ESTIMATED TO BE 080/9.  THE HURRICANE HAS MOVED ON
 A MORE EASTERLY TRACK THAN ANTICIPATED...IN PART DUE TO A LACK OF
 MID-LEVEL RIDGING TO ITS SOUTHEAST...RESULTING IN A MORE ZONAL
 STEERING CURRENT THAN EXPECTED.  HOWEVER AS A 500 MB TROUGH MOVES
 INTO THE CANADIAN MARITIME DURING THE NEXT DAY OR SO...A GRADUAL
 TURN TO THE LEFT...AHEAD OF THIS TROUGH...IS ANTICIPATED.  THE
 OFFICIAL TRACK FORECAST IS IN GOOD AGREEMENT WITH THE LATEST
 GFS...WHICH APPEARS TO HAVE A GOOD INITIALIZATION OF THE TROPICAL
 CYCLONE.
 
 FORECASTER PASCH
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      16/1500Z 36.7N  62.4W    75 KT
  12HR VT     17/0000Z 37.2N  60.9W    70 KT
  24HR VT     17/1200Z 38.3N  58.8W    65 KT
  36HR VT     18/0000Z 41.0N  54.5W    55 KT...BECOMING EXTRATROPICAL
  48HR VT     18/1200Z 46.0N  48.0W    50 KT...EXTRATROPICAL
  72HR VT     19/1200Z 55.0N  36.0W    45 KT...EXTRATROPICAL
  96HR VT     20/1200Z...ABSORBED
  
  
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