000 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