000 WTPZ43 KNHC 050245 TCDEP3 HURRICANE FELICIA DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP082009 800 PM PDT TUE AUG 04 2009 SATELLITE IMAGERY INDICATES THAT FELICIA HAS CONTINUED TO RAPIDLY INTENSIFY OVER THE PAST SEVERAL HOURS. IN THE LAST COUPLE OF HOURS A BAND OF VERY COLD CLOUD TOPS HAS DEVELOPED EAST OF THE CENTER AND WRAPPED MORE THAN HALFWAY AROUND AN EYE THAT IS NOW APPARENT IN INFRARED IMAGERY. BASED ON SATELLITE TRENDS AND A DATA-T NUMBER OF 5.0 FROM A 0130 UTC SPECIAL DVORAK CLASSIFICATION BY TAFB...THE INITIAL INTENSITY IS RAISED TO 85 KT FOR THIS PACKAGE. FELICIA APPEARS TO HAVE SLOWED DOWN AND JOGGED TOWARD THE WEST EARLIER TODAY AS IT BEGAN INTENSIFYING...HOWEVER THE CYCLONE NOW APPEARS TO BE MOVING ALONG A HEADING OF 285/10...SLIGHTLY TO THE NORTH OF THE PREVIOUS PACKAGE. A WEAKNESS IN THE SUBTROPICAL RIDGE CENTERED ALONG 130W IS ASSOCIATED WITH A VERY AMPLIFIED DEEP-LAYER TROUGH LOCATED OFF THE U.S. WEST COAST. THIS TROUGH WILL WEAKEN AND MOVE EASTWARD OVER THE NEXT COUPLE OF DAYS...ALLOWING THE SUBTROPICAL RIDGE TO RE-BUILD NORTH OF FELICIA IN 48 TO 72 HOURS. MOST OF THE TRACK GUIDANCE IS TIGHTLY CLUSTERED AROUND A WEST-NORTHWEST TRACK THROUGH 72 HOURS...FOLLOWED BY A TURN TOWARD THE WEST AT DAYS 4 AND 5. LATE IN THE PERIOD...FELICIA'S TRACK MAY BE IMPACTED BY AN UPPER-LEVEL LOW THAT DEVELOPS NORTHEAST OF THE HAWAIIAN ISLANDS IN MOST OF THE GLOBAL MODELS. HOWEVER...THERE IS SIGNIFICANT UNCERTAINTY IN THE POSITION AND INTENSITY OF THIS FEATURE AND ITS IMPACT ON THE CYCLONE'S TRACK. THE OFFICIAL FORECAST IS SHIFTED NORTH OF THE PREVIOUS PACKAGE TO ACCOUNT FOR THE INITIAL POSITION AND A NORTHWARD SHIFT IN THE DYNAMICAL MODEL CONSENSUS...TVCN. RAPID INTENSIFICATION APPEARS TO BE CONTINUING...AND ENVIRONMENTAL CONDITIONS APPEAR TO BE FAVORABLE FOR CONTINUED STRENGTHENING DURING THE NEXT 36 HOURS OR SO. THE SHIPS RAPID INTENSIFICATION INDEX SHOWS A 45 PERCENT CHANCE OF A 30-KT INCREASE IN INTENSITY OVER THE NEXT 24 HOURS. WHILE THIS IS LOWER THAN IT WAS WITH THE LAST PACKAGE...IT IS STILL 6 TIMES GREATER THAN THE SAMPLE MEAN. THE DYNAMICAL MODELS CONTINUE TO BE LESS AGGRESSIVE WITH THE INTENSITY OF FELICIA...AND THE OFFICIAL FORECAST IS ABOVE EVEN THE HIGHER SHIPS GUIDANCE FOR THIS PACKAGE BASED ON THE CURRENT SATELLITE TRENDS. LATER IN THE PERIOD THE CYCLONE WILL ENCOUNTER COOLER WATERS...WHICH SHOULD RESULT IN A SLOW WEAKENING AT DAY 3 AND BEYOND. FORECAST POSITIONS AND MAX WINDS INITIAL 05/0300Z 12.8N 127.2W 85 KT 12HR VT 05/1200Z 13.4N 128.8W 95 KT 24HR VT 06/0000Z 14.4N 130.5W 100 KT 36HR VT 06/1200Z 15.3N 132.2W 100 KT 48HR VT 07/0000Z 16.1N 133.9W 95 KT 72HR VT 08/0000Z 17.5N 138.0W 85 KT 96HR VT 09/0000Z 18.0N 143.5W 75 KT 120HR VT 10/0000Z 18.0N 149.5W 60 KT $$ FORECASTER BRENNAN