WTPA42 PHFO 232046
TCDCP2

HURRICANE IOKE DISCUSSION NUMBER  16
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP012006
1100 AM HST WED AUG 23 2006

SATELLITE IMAGES SHOW A CIRRUS FILLED EYE WITH THE DEEPEST
CONVECTION IN THE NORTHERN EYEWALL.  A MICROWAVE PASS FROM AMSU AT
1452 UTC ALSO INDICATED THAT THE EYEWALL WAS OPEN IN THE SOUTHERN
SEMICIRCLE.  SUBJECTIVE DVORAK INTENSITY ESTIMATES CAME IN AT 90 KT
FROM CPHC...AFWA AND JTWC.  THE SAB ESTIMATE WAS 102 KT.  THE
OBJECTIVE AODT ESTIMATE WAS 90 KT. BASED ON THE CONSENSUS...THE
INITIAL INTENSITY HAS BEEN HELD AT 90 KT.

IOKE CONTINUES TO MOVE TOWARD THE NORTHWEST...316 DEGREES...AT 6 KT
TO THE SOUTH OF A WEAK SUBTROPICAL RIDGE AND TOWARD A LOW PRESSURE
SYSTEM WEST OF THE DATELINE.  THE DYNAMIC MODELS ARE TIGHTLY
CLUSTERED WITH A CONTINUATION OF THE NORTHWESTWARD TRACK OVER THE
NEXT 36 HOURS FOLLOWED BY A TURN TOWARD THE SOUTHWEST AS
A NORTHEAST TO SOUTHWEST RIDGE BUILDS NORTHWEST OF THE HURRICANE. 
THE FORECAST TRACK CLOSELY FOLLOWS THE DYNAMIC CONSENSUS...
GUNS...GUNA AND CONU...WITH THE ONLY DIFFERENCE BEING A SLIGHTLY
SLOWER MOTION AT DAYS 4 AND 5.  OTHER THAN A SLIGHT NORTHWARD NUDGE
INITIALLY...THIS TRACK IS CLOSE TO THE PREVIOUS FORECAST. 

CIMSS SHEAR ANALYSIS VALUES HAVE BEEN SLOWLY DECREASING...DOWN TO
4.9 M/S AT 1800 UTC...AND MODELS KEEP LOW SHEAR VALUES THROUGH THE
NEXT 36 HOURS FOLLOWED BY THE INTRODUCTION OF NORTHERLY SHEAR
AFTERWARD.  IOKE IS ALSO EXPECTED TO REMAIN OVER SST VALUES AT
AROUND 28C WHICH IS MORE THAN ENOUGH TO MAINTAIN HURRICANE
INTENSITY.  THUS...OVER THE NEXT 1 TO 2 DAYS THE FORECAST MAINTAINS
THE CURRENT INTENSITY OF 90 KT WHICH IS ROUGHLY IN LINE WITH THE
CONSENSUS OF THE OBJECTIVE AIDS.  THE INTENSITY GUIDANCE DIVERGES
CONSIDERABLY FROM 48 HOURS WITH SHIPS DROPPING IOKE DOWN TO TROPICAL
STORM STRENGTH AND THE DYNAMIC MODELS SHOWING SLIGHT
INTENSIFICATION THROUGH 120 HOURS.  SHIPS GUIDANCE WILL NOT BE
FOLLOWED IN THE LONGER RANGE DUE TO QUESTIONABLE RESULTS IN THE SST
POTENTIAL COMPONENT.  HOWEVER...SINCE VERTICAL SHEAR IS EXPECTED TO
INCREASE IN RESPONSE TO A STRONG UPPER LEVEL TROUGH DIGGING BETWEEN
160W TO 170W...THE FORECAST CALLS FOR IOKE TO WEAKEN SLOWLY FROM
DAYS 2 THROUGH 5.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      23/2100Z 17.8N 171.1W    90 KT
 12HR VT     24/0600Z 18.5N 171.8W    90 KT
 24HR VT     24/1800Z 19.1N 173.0W    90 KT
 36HR VT     25/0600Z 19.7N 174.2W    90 KT
 48HR VT     25/1800Z 20.0N 175.6W    90 KT
 72HR VT     26/1800Z 19.9N 178.4W    85 KT
 96HR VT     27/1800Z 18.6N 179.0E    75 KT
120HR VT     28/1800Z 17.7N 176.1E    65 KT
 
$$
FORECASTER KODAMA