WTPA42 PHFO 211447
TCDCP2

HURRICANE IOKE DISCUSSION NUMBER   7
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP012006
500 AM HST MON AUG 21 2006

ALL INDICATIONS ARE THAT HURRICANE IOKE IS CONTINUING TO INTENSIFY.
THE LATEST IR IMAGERY FROM THE GOES11 AT 1400 UTC CONTINUES TO SHOW
THE EYE IS BECOMING BETTER DEFINED. THIS EYE IS SURROUNDED BY A RING
OF DEEP CONVECTION WITH CLOUD TOP TEMPERATURES ESTIMATED TO BE AS
LOW AS MINUS 79C. AGAIN...THE SATELLITE FIXES FROM ALL AGENCIES
WERE TIGHTLY CLUSTERED IN THE LOCATION OF THIS EYE. THE SATELLITE 
AGENCIES PROVIDED ESTIMATED CI VALUES RANGING FROM 4.0 TO 5.0. AODT 
YIELDED 5.5 AT PHFO. BASED ON THESE SUBJECTIVE SATELLITE ESTIMATES 
AND THE IMPROVING APPEARANCE OF IOKE...THE INITIAL INTENSITY WAS 
INCREASED TO 75 KT. SLIGHT ADJUSTMENT WERE ALSO MADE TO THE INITIAL 
WIND RADII...MAINLY IN THE SOUTHWEST QUADRANT.
 
THE INITIAL MOTION OF IOKE IS 295 DEG AT 10 KT. THE PRIMARY DYNAMIC
AND GLOBAL TRACK MODELS HAVE A RATHER SMALL SPREAD THROUGH DAY 5.
THIS NEW FORECAST TRACK IS VERY SIMILAR TO THE PREVIOUS ONE. THE
CONSENSUS MODEL...CONU...WAS AGAIN FOLLOWED CLOSELY FOR THIS
ADVISORY. THIS CONSENSUS ALSO HAPPENS TO BE VERY CLOSE TO THE GFSI
THROUGH DAY 4. THE GFDI LIES TO THE RIGHT AND THE UKMET LIES TO THE
LEFT OF CONU. THE MODELS CONTINUE TO SHOW THE INFLUENCE OF A
MIDDLE AND UPPER LEVEL TROUGH NOW LOCATED NORTHWEST OF THE
HURRICANE. THERE IS ALSO AN UPPER LEVEL  RIDGE LOCATED EAST 
NORTHEAST OF IOKE ALONG LATITUDE 25N. THE DEEP LAYER STEERING FROM 
THESE FEATURES WILL MAINTAIN THE PRESENT MOVEMENT OF IOKE TOWARD THE 
WEST-NORTHWEST FOR THE NEXT 2 TO 3 DAYS. HOWEVER...A WEAKNESS IN THE 
STEERING IS EXPECTED TO RESULT IN SOME SLOWING OF THE HURRICANE 
BEYOND DAY 3. IN FACT...AT DAY 5 THE MODELS ARE SUGGESTING IOKE MAY 
SLOW TO A CRAWL.
 
THE SHIPS MODEL HAS BACKED OFF SOMEWHAT ON THE FORECAST INTENSITY OF
IOKE DURING THE NEXT 36 TO 72 HOURS. HOWEVER...NO ADJUSTMENTS WILL
BE MADE IN THE INTENSITY FORECAST IN THIS PACKAGE AS COMPARED WITH
THE PREVIOUS FORECAST. INCREASING VERTICAL WIND SHEAR WILL LIKELY 
PLAY A MAJOR ROLE IN THE EXPECTED WEAKENING OF IOKE FROM DAYS 3 
THROUGH 5.
 
ALL INTERESTS IN THE VICINITY OF JOHNSTON ISLAND SHOULD IMMEDIATELY
PREPARE FOR THE ONSET OF THE OUTER WINDS...HEAVY RAINFALL AND 
DANGEROUS SEAS FROM AN INTENSIFYING IOKE. THE FORECAST CLOSEST 
APPROACH OF THIS HURRICANE TO THAT ISLAND WILL TAKE PLACE IN LESS 
THAN 30 HOURS. THE PRESENT TRACK WOULD TAKE IOKE SOUTHWEST OF 
JOHNSTON ISLAND...WHICH WOULD PLACE THE ISLAND IN THE RIGHT FRONT 
QUADRANT OF THE GALE WIND RADII OF THE HURRICANE. THE FORECAST 50 KT 
WIND RADII IS ALSO CLOSE TO THIS ISLAND AS IOKE PASSES BY TUESDAY
MORNING.
  
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      21/1500Z 12.3N 165.8W    75 KT
 12HR VT     22/0000Z 13.4N 167.3W    85 KT
 24HR VT     22/1200Z 15.0N 169.2W    95 KT
 36HR VT     23/0000Z 16.3N 170.8W   100 KT
 48HR VT     23/1200Z 17.4N 172.0W   100 KT
 72HR VT     24/1200Z 19.3N 174.1W    90 KT
 96HR VT     25/1200Z 21.3N 175.8W    80 KT
120HR VT     26/1200Z 23.0N 177.4W    70 KT
 
$$
FORECASTER HOUSTON