473 
 WTPZ43 KNHC 081444
 TCDEP3
 HURRICANE FELICIA DISCUSSION NUMBER  20
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP082009
 800 AM PDT SAT AUG 08 2009
  
 FELICIA IS MAINTAINING ITS STRUCTURE OVER RELATIVELY COOL WATERS
 WITH A RATHER SYMMETRIC APPEARANCE ON SATELLITE. ALTHOUGH THE EYE
 HAS FILLED SOMEWHAT...CLOUD TOP TEMPERATURES IN THE EYEWALL HAVE
 ACTUALLY COOLED DURING THE PAST FEW HOURS. SATELLITE INTENSITY
 ESTIMATES HAVE NOT CHANGED APPRECIABLY...AND THE INITIAL WIND SPEED
 WILL BE KEPT AT 80 KT. IT WILL BE INTERESTING TO SEE WHAT THE AIR
 FORCE RESERVE HURRICANE HUNTERS FIND WHEN THEY ENTER THE EYE THIS
 AFTERNOON...AS THERE IS A DECENT SPREAD IN THE LATEST SATELLITE
 INTENSITY ESTIMATES.
 
 THE GRADUAL WESTWARD TURN CONTINUES...AND THE HURRICANE IS NOW
 MOVING 280/13. A WESTWARD MOTION IS LIKELY FOR THE NEXT SEVERAL
 DAYS AS A MID-LEVEL RIDGE BUILDS TO THE NORTH OF CYCLONE. IN A
 COUPLE OF DAYS...THE GLOBAL MODELS SUGGEST THAT FELICIA WILL
 ENCOUNTER INCREASING UPPER-LEVEL WESTERLIES...A BREAK IN THE
 SUBTROPICAL RIDGE...AND THE EASTERN PORTION OF A MID-LEVEL HIGH
 NEAR HAWAII. THIS PATTERN COULD BRING ABOUT A RELATIVELY FAST
 DEMISE OF THE CYCLONE...AS THE MIDDLE TO UPPER PART OF THE STORM IS
 HELD TO EAST WHILE THE LOW-LEVEL CIRCULATION CONTINUES WESTWARD.
 WHILE THERE ARE DIFFERENCES IN THE DETAILS OF THE TRACK AS THE STORM
 APPROACHES THE HAWAIIAN ISLANDS...THE MODEL CONSENSUS REMAINS
 UNCHANGED...AND THE OFFICIAL FORECAST IS BASICALLY AN UPDATE OF THE
 PREVIOUS FORECAST.
 
 WIND SHEAR NEAR THE HURRICANE IS FORECAST TO REMAIN LOW FOR ABOUT
 THE NEXT 24 HOURS. IN COMBINATION WITH MARGINAL SSTS...THESE
 FACTORS CALL FOR A RELATIVELY SLOW WEAKENING. THEREAFTER...WATER
 TEMPERATURES ARE FORECAST TO SLOWLY RISE...WHICH WOULD TEND TO
 DECREASE THE RATE OF WEAKENING. HOWEVER...VERTICAL WIND SHEAR IS
 EXPECTED TO INCREASE AS WELL. IN FACT...THE HIGH-RESOLUTION
 HURRICANE MODELS SUGGEST THAT THIS SHEAR WILL CAUSE THE STORM TO
 SHEAR APART IN 36-48 HOURS...AND THE CONTINUED EFFECTS OF SHEAR
 COULD RESULT IN TOTAL DISSIPATION OF THE SYSTEM IN ABOUT 5 DAYS.
 THE OFFICIAL FORECAST IS ONLY A LITTLE BIT DIFFERENT FROM THE
 PREVIOUS PACKAGE AND IS NEAR THE INTENSITY CONSENSUS. 
 
 DATA FROM A G-IV MISSION THIS MORNING TO THE NORTH AND EAST OF
 HAWAII SHOULD MAKE ITS WAY INTO THE 1200 UTC GLOBAL MODEL GUIDANCE
 THIS AFTERNOON.  
 
 FUTURE DISCUSSIONS ON THIS SYSTEM WILL BE ISSUED BY THE CENTRAL
 PACIFIC HURRICANE CENTER UNDER AWIPS HEADER TCDCP2 AND WMO HEADER
 WTPA42 PHFO. 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      08/1500Z 19.3N 140.8W    80 KT
  12HR VT     09/0000Z 19.6N 142.8W    70 KT
  24HR VT     09/1200Z 19.7N 145.4W    65 KT
  36HR VT     10/0000Z 19.8N 148.0W    55 KT
  48HR VT     10/1200Z 19.7N 150.5W    45 KT
  72HR VT     11/1200Z 19.5N 156.0W    30 KT
  96HR VT     12/1200Z 19.5N 161.0W    25 KT...REMNANT LOW
 120HR VT     13/1200Z 20.5N 166.5W    20 KT...REMNANT LOW
  
 $$
 FORECASTER BLAKE