WTPA44 PHFO 081440 TCDCP4 TROPICAL STORM JIMENA DISCUSSION NUMBER 52 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP132015 500 AM HST TUE SEP 08 2015 HIGH CLOUDS ACROSS THE SOUTHEAST QUADRANT OF JIMENA THINNED ENOUGH OVER THE PAST SIX HOURS TO OFFER GOOD VIEWS OF LOW CLOUD SWIRLS IN ANIMATION WHICH...WHEN ADDED TO ANALYSIS OF LOW CLOUD SWIRLS ACROSS THE WEST SEMICIRCLE...CONTRIBUTE TO OVERALL FIX CONFIDENCE FOR THE 1200 UTC ANALYSIS CYCLE. HOWEVER...AN 0700 UTC ASCAT PASS ACROSS JIMENA...RECEIVED A BIT TOO LATE FOR THE LAST ADVISORY...SHOWED A SLIGHTLY MORE INTENSE SYSTEM AND PLACED THE LLCC FARTHER SOUTH AND WEST THAN ESTIMATED VIA SATELLITE ANALYSIS ALONE. A 1 KM RESOLUTION VIIRS IMAGE AT 1146 UTC ALLOWED A VIEW OF ALMOST ALL OF THE LOW CLOUD CIRCULATION...SHOWING THE LLCC WAS INDEED NOTICEABLY WEST OF ANY MID AND UPPER LEVEL CIRCULATION NOTED BY THE SATELLITE CENTERS. SINCE THE FINAL 1200 UTC POSITION AND STRENGTH WOULD HAVE RESULTED IN UNREPRESENTATIVE MOTION AND INTENSITY FLUCTUATIONS...WE REANALYZED THE PREVIOUS 0600 UTC...0000 UTC AND 1800 UTC POSITIONS AND INTENSITIES. SUBJECTIVE DVORAK SATELLITE INTENSITY ESTIMATES WERE ONCE AGAIN ALL 2.5...35 KT...FROM THE SATELLITE CENTERS...WHILE UW-CIMSS ADT ESTIMATED 40 KT. A RESPECTABLE SWATH OF 45 KT WINDS WAS NOTED ACROSS THE NORTHEAST QUADRANT IN THE ASCAT PASS AND...AS A RESULT OF THE REANALYSIS PROCESS...AN INITIAL INTENSITY OF 45 KT IS ASSIGNED FOR THIS ADVISORY. IT IS LIKELY THAT JIMENA ACTUALLY MAINTAINED A STEADY 45 KT INTENSITY OVER THE PAST 24 HOURS. AFTER REANALYSIS...THE 12 HOUR MOTION IS 275/07 KT...SLIGHTLY FASTER AND MORE WESTERLY THAN DEPICTED BEFORE. JIMENA IS IN AN INCREASINGLY HOSTILE WEST TO SOUTHWEST SHEAR ENVIRONMENT...RANGING FROM 24 KT TO 32 KT...FROM SHIPS AND UW-CIMSS RESPECTIVELY. SINCE SHIPS FORECASTS SHEAR INCREASING TO OVER 40 KT AT 48 HOURS AND OVER 50 KT AT 72 HOURS...IT IS ONCE AGAIN DIFFICULT TO SEE HOW THIS SYSTEM COULD REMAIN INTACT THROUGH A FIVE DAY FORECAST TRACK. HOWEVER...JIMENA HAS PROVEN TO BE QUITE RESILIENT SO FAR. CONSENSUS TRACK GUIDANCE SHIFTED NOTICEABLE TO THE WEST...AND JUST SLIGHTLY TO THE SOUTH...PROMPTING US TO ADD A A BIT OF FORWARD MOTION AND TO NUDGE THE FORECAST TRACK TO THE LEFT AFTER 12 HOURS. A SMALL DEVIATION TO THE RIGHT AT 12 HOURS WAS MADE TO ACCOUNT FOR INITIAL MOTION. THE FINAL FORECAST TRACK FOLLOWS CONSENSUS MORE CLOSELY THAN BEFORE...BUT REMAINS JUST TO THE RIGHT OF IT. JIMENA IS FORECAST TO GRADUALLY WEAKEN THROUGH THE NEXT FIVE DAYS...BECOMING AN EXTRATROPICAL LOW BY DAY 4. THE FORESEEN SHEAR INCREASE BY DAY TWO MAY SHORTEN THIS LIFESPAN. THIS ADVISORY WEAKENS JIMENA TO A DEPRESSION BY 36 HOURS...LIKE LAST TIME...IN SPITE OF THE INITIAL INTENSITY BUMP. THIS FOLLOWS MOST GUIDANCE...INCLUDING SHIPS...THROUGH 36 HOURS. HOWEVER...SHIPS THEN QUICKLY DISSIPATES JIMENA AT 48 HOURS. WE ARE NOT QUITE THAT BOLD. EITHER WAY...WHATEVER IS LEFT OF JIMENA WILL BE DRAWN POLEWARD ALONG THE EASTERN FLANK OF LOW PRESSURE DEVELOPING NORTH OF THE NORTHWESTERN HAWAIIAN ISLANDS FROM DAYS THREE TO FIVE. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 26.5N 152.7W 45 KT 50 MPH 12H 09/0000Z 26.6N 153.8W 40 KT 45 MPH 24H 09/1200Z 26.1N 155.5W 35 KT 40 MPH 36H 10/0000Z 25.7N 157.2W 30 KT 35 MPH 48H 10/1200Z 25.5N 158.9W 30 KT 35 MPH 72H 11/1200Z 25.9N 162.2W 25 KT 30 MPH 96H 12/1200Z 27.6N 165.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 13/1200Z 30.5N 166.9W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ FORECASTER POWELL