824 
 WTPA43 PHFO 190905
 TCDCP3
 
 TROPICAL DEPRESSION TWO-C DISCUSSION NUMBER   2
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP022006
 1100 PM HST MON SEP 18 2006
 
 TROPICAL DEPRESSION TWO-C CONTINUES TO STRENGTHEN AS IT MOVES 
 WESTWARD WELL SOUTH OF THE HAWAIIAN ISLANDS. OVER THE PAST SIX 
 HOURS...TWO-C HAS STARTED TO SHOW SIGNS OF BETTER ORGANIZATION AND 
 CONVECTION NEAR THE CENTER HAS INCREASED. CLOUD COVER ASSOCIATED 
 WITH THE INCREASE IN CONVECTION HAS ALSO MADE IT MORE DIFFICULT TO 
 LOCATE THE EXACT CENTER. THE MAXIMUM WIND SPEED WAS INCREASED TO 30 
 KNOTS BASED ON AGENCY FIXES OF 1.5 AND QUIKSCAT DATA. WINDSAT DATA 
 AT 0416 UTC DID INDICATE SOME 40 KNOT WINDS NORTH OF THE CENTER NEAR 
 10.5N LATITUDE...BUT THESE SEEMED UNREASONABLE AND WERE DISCOUNTED. 
 
 THE FORECAST TRACK OF TWO-C HAS BEEN ADJUSTED SOUTHWARD OR TO THE 
 LEFT OF THE PREVIOUS TRACK...WHICH RELIED EXCLUSIVELY ON THE BETA 
 ADVECTION AND PERSISTENCE/CLIMATOLOGY MODELS. THE CURRENT GUIDANCE 
 SUITE...INCLUDING GFDL...GFS...UKMET...AND CONU FORECASTS...SHOWS A 
 CONSIDERABLE SHIFT TOWARD THE SOUTH BEYOND 36 HOURS...TAKING TWO-C 
 ON A MORE WESTWARD TRACK. DEEP LAYER MEAN WINDS THAT WOULD HELP TO 
 STEER THIS STORM ARE EXPECTED TO REMAIN ALMOST FROM DUE EAST...WHICH 
 ADDS CREDENCE TO THE MORE WESTWARD MOVEMENT. THE CURRENT FORECAST 
 TRACK REMAINS CLOSE TO THE PREVIOUS TRACK THROUGH 36 HOURS AND 
 SHIFTS CLOSER TO THE GFDL TRACK THEREAFTER...WHICH IS NOT QUITE AS 
 FAR SOUTH AS THE CONU.
 
 WIND RADII WERE ALSO EXPANDED PRIMARILY THROUGH 36 HOURS IN RESPONSE 
 TO THE INCREASED IN INTENSITY AND QUIKSCAT DATA. WIND RADII REMAIN 
 LARGEST IN THE NORTHEAST QUADRANT OF THE STORM...WHERE THE GRADIENT 
 BETWEEN THE STORM AND HIGH PRESSURE TO THE NORTHEAST IS THE 
 STRONGEST.
 
 THE FORECAST INTENSITY WAS INCREASED THROUGH 36 HOURS IN RESPONSE TO 
 THE INCREASE IN INITIAL INTENSITY. THERE IS VERY LITTLE SHEAR NEAR 
 TWO-C AT THE MOMENT AND MODELS ARE IN GOOD AGREEMENT THAT TWO-C WILL 
 ENCOUNTER LITTLE TO NO VERTICAL SHEAR OVER THE NEXT SEVERAL DAYS.  
 EXPERIMENTAL VERTICAL SHEAR ESTIMATES FROM UW-CIMMS CONCUR...AND 
 LIST DEVELOPMENT OUTLOOK AS VERY FAVORABLE IN THE NEAR TERM. TWO-C 
 IS SPINNING OVER SSTS OF 28 DEGREES CELSIUS AND GIVEN ITS FORECAST 
 TRACK WILL REMAIN OVER WATER NEAR 28 DEGREES CELSIUS. ALL SIGNS 
 THEREFORE...ARE FAVORABLE FOR ADDITIONAL DEVELOPMENT. AS IT 
 STANDS...TWO-C IS EXPECTED TO BECOME A TROPICAL STORM EARLY 
 TUESDAY...AND REACH HURRICANE STRENGTH WEDNESDAY.
 
 ITS PROJECTED PATH THROUGH 120 HOURS KEEPS TWO-C OVER WATER AND AWAY 
 FROM ANY MAJOR PACIFIC ISLANDS. THE SOUTHWARD ADJUSTMENT OF THE 
 FORECAST TRACK AFTER 36 HOURS ALSO PLACES TWO-C FURTHER AWAY FROM 
 JOHNSTON ISLAND.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      19/0900Z 10.0N 158.1W    30 KT
  12HR VT     19/1800Z 10.3N 159.8W    40 KT
  24HR VT     20/0600Z 10.8N 162.0W    45 KT
  36HR VT     20/1800Z 11.4N 164.2W    55 KT
  48HR VT     21/0600Z 12.0N 166.5W    65 KT
  72HR VT     22/0600Z 13.4N 171.1W    75 KT
  96HR VT     23/0600Z 14.4N 174.3W    80 KT
 120HR VT     24/0600Z 14.8N 176.5W    80 KT
  
 $$
 FORECASTER TANABE/HOUSTON