020 
 WTPA42 PHFO 041446
 TCDCP2
 
 TROPICAL DEPRESSION ONE-C DISCUSSION NUMBER   4
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI
 5 AM HST THU AUG 04 2005
  
 ONE-C HAS BECOME DIFFICULT TO LOCATE...WITH THE INITIAL POSITION 
 REPRESENTING A COMPROMISE BETWEEN WHAT APPEARS TO BE A REMNANT 
 MID-LEVEL CIRCULATION AND A POSSIBLE LLCC BEGINNING TO EMERGE FROM 
 BENEATH HIGH CLOUDS A BIT FARTHER WEST. THE REMNANT MID-LEVEL 
 CIRCULATION WAS THE FEATURE KEYED UPON FOR MOST SATELLITE FIXES. THE 
 EMERGING LLCC IS A VERY RECENT DEVELOPMENT...OCCURRING WITHIN THE 
 PAST HOUR OR SO. A SINGLE CB MARKS THE WESTERN FRINGE OF THIS LLCC. 
 CONFIDENCE IS NOT YET HIGH ENOUGH TO SUDDENLY SWITCH THE INITIAL 
 POSITION TO THIS NEW SUSPECTED FEATURE...HENCE THE COMPROMISE. 
 
 ONCE AGAIN...TRACK GUIDANCE VARIES WIDELY...WITH DEEP LAYER GUIDANCE 
 WANTING TO CURVE ONE-C TO THE NORTH LONG BEFORE REACHING THE 
 ISLANDS. DEEP GUIDANCE WOULD ONLY BE USEFUL WITH A VIGOROUSLY 
 CONVECTIVE ONE-C. UNTIL VIGOROUS AND PERSISTENT CONVECTION 
 OCCURS...WE WILL USE SHALLOW-BASED GUIDANCE WHICH IS CONSIDERABLY 
 FURTHER TO THE LEFT. THE OFFICIAL TRACK REMAINS VERY CLOSE TO THE 
 LAST ONE...JUST TO THE RIGHT OF GFDL. THIS WILL TAKE ONE-C 
 COMFORTABLY SOUTH OF THE MAIN HAWAIIAN ISLANDS.
 
 SINCE THE PREVIOUS FORECAST FOR STRENGTHENING ONE-C TO TROPICAL 
 STORM THRESHOLD WAS BASED ON AN ANTICIPATED UPSURGE OF CONVECTION 
 OVERNIGHT...THE CURRENT FORECAST NOW MAXES ONE-C AT ONLY 30 KT FROM 
 12 THROUGH 48 HOURS OUT. THIS IS IN LINE WITH MOST INTENSITY 
 GUIDANCE...ALTHOUGH GFDL WANTS TO SUDDENLY STRENGTHEN ONE-C TO 40 
 KTS RIGHT AT 72 HOURS AFTER GRADUAL WEAKENING TO 19 KTS AT 48 HOURS. 
 WE ANTICIPATE A SLOW DISSIPATION OF ONE-C THROUGH 120 HOURS...WITH 
 LOW LEVEL TRADES PROVIDING PRIMARY STEERING.
  
 FORECASTER POWELL
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      04/1500Z 15.2N 143.0W    25 KT
  12HR VT     05/0000Z 15.5N 144.5W    30 KT
  24HR VT     05/1200Z 15.6N 146.8W    30 KT
  36HR VT     06/0000Z 15.6N 149.3W    30 KT
  48HR VT     06/1200Z 15.6N 152.0W    30 KT
  72HR VT     07/1200Z 15.5N 157.4W    25 KT
  96HR VT     08/1200Z 14.9N 162.8W    20 KT...DISSIPATING
 120HR VT     09/1200Z 14.2N 168.0W    15 KT...REMNANT LOW
  
  
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