876 
 WTPA44 PHFO 052039
 TCDCP4
 
 HURRICANE JIMENA DISCUSSION NUMBER  41
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP132015
 1100 AM HST SAT SEP 05 2015
  
 JIMENA HAS ALL THE SIGNS OF A SHEARED WEAKENING TROPICAL CYCLONE IN
 THE SATELLITE IMAGERY THIS MORNING. LOW LEVEL CLOUD LINES IN THE
 VISIBLE IMAGERY INDICATE THAT THE LOW LEVEL CIRCULATION CENTER IS
 SOUTHWEST OF THE REMAINING DEEP CONVECTION AND THE UPPER LEVEL
 OUTFLOW IS LIMITED TO JUST THE NORTHEASTERN SEMICIRCLE. THE LOW
 LEVEL CENTER POSITION IS SUPPORTED BY 37 GHZ DATA IN THE SSMI PASSES
 FROM 1431...1611 AND 1616 UTC. THE DETERIORATING CONDITION OF JIMENA
 IS NOT SURPRISING CONSIDERING 27 KT OF VERTICAL SHEAR FROM THE
 WEST-SOUTHWEST BASED ON THE CIMSS 1800 UTC ANALYSIS. DVORAK
 INTENSITY ESTIMATES CHECKED IN AT 4.5/77 KT FROM PHFO AND JTWC...AND
 3.5/55 KT FROM SAB. THE UW/CIMSS 1800 UTC ADT ESTIMATE WAS 59 KT.
 BASED ON AN AVERAGE OF THESE ESTIMATES...THE CURRENT INTENSITY FOR
 THIS ADVISORY IS 65 KT WHICH IS BARELY A HURRICANE...AND THIS MAY BE
 GENEROUS. SATELLITE ALTIMETER DATA FROM ABOUT 1530 UTC WERE USED TO
 EXPAND THE 12 FT SEAS RADII IN THE NORTHERN SEMICIRCLE.
 
 THE INITIAL MOTION FOR THIS ADVISORY IS 325/7 KT AS JIMENA MOVES
 BETWEEN A LARGE MID- AND UPPER-LEVEL TROUGH TO THE WEST AND A RIDGE
 TO THE NORTH AND EAST. THE GLOBAL MODELS STRENGTHEN THE RIDGE TO THE
 NORTH...THEN DEVELOP AN ANTICYLONE TO THE NORTHWEST OF JIMENA AFTER
 72 HOURS. THIS WILL RESULT IN A WESTWARD TURN FOLLOWED BY A SLIGHTLY
 SOUTH OF WEST TRACK IN THE 96 TO 120 HOUR TIME FRAME. THE MAIN
 DYNAMICAL MODELS ARE IN GENERAL AGREEMENT WITH THIS SCENARIO THROUGH
 48 HOURS WITH INCREASING SPREAD IN THE SOLUTIONS AFTERWARD. THE
 CURRENT FORECAST IS CLOSE TO THE PREVIOUS FORECAST WITH SMALL NUDGES
 TOWARD THE GFS AND ECMWF CONSENSUS...GFEX...THROUGHOUT THE FORECAST
 PERIOD.
 
 THE LARGE MID- AND UPPER LEVEL TROUGH WEST OF THE MAIN HAWAIIAN
 ISLANDS IS RESULTING IN WEST-SOUTHWESTERLY VERTICAL WIND SHEAR
 ACROSS JIMENA. THE WEST-SOUTHWESTERLY SHEAR IS EXPECTED TO
 CONTINUE...THEN GRADUALLY SHIFT TO THE WEST-NORTHWEST. THE FORECAST
 TRACK ALSO KEEPS THE TROPICAL CYCLONE OVER SEA SURFACE TEMPERATURES
 JUST ABOVE 26.5C. THE COMBINED PERSISTENCE OF THE VERTICAL WIND
 SHEAR AND THE BARELY ADEQUATE SEA SURFACE TEMPERATURES SHOULD
 CONTINUE TO RESULT IN A WEAKENING OF JIMENA THROUGH THE FORECAST
 PERIOD. THE MAIN QUESTION AT THIS TIME IS HOW FAST THE WEAKENING
 WILL OCCUR. SHIPS IS THE MOST AGGRESSIVE AND CALLS FOR DISSIPATION
 BY 72 HOURS. HWRF AND GFDL ALSO SHOW WEAKENING BUT ARE MORE
 CONSERVATIVE THAN SHIPS. THE FORECAST WEAKENS JIMENA STEADILY AND IS
 CLOSE TO THE PREVIOUS FORECAST AND THE INTENSITY CONSENSUS.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  05/2100Z 21.8N 146.7W   65 KT  75 MPH
  12H  06/0600Z 22.7N 147.3W   60 KT  70 MPH
  24H  06/1800Z 23.9N 148.2W   55 KT  65 MPH
  36H  07/0600Z 24.8N 149.3W   50 KT  60 MPH
  48H  07/1800Z 25.2N 150.3W   45 KT  50 MPH
  72H  08/1800Z 25.1N 153.0W   35 KT  40 MPH
  96H  09/1800Z 24.5N 156.5W   35 KT  40 MPH
 120H  10/1800Z 24.5N 160.0W   30 KT  35 MPH
  
 $$
 FORECASTER KODAMA