426 
 WTPA42 PHFO 250243
 TCDCP2
 
 TROPICAL STORM NEKI DISCUSSION NUMBER  26
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP032009
 500 PM HST SAT OCT 24 2009
 
 DEEP CONVECTION HAS REMAINED PERSISTENT NEAR THE CENTER OF NEKI
 THROUGHOUT THE DAY. IN FACT...A 24 HOUR LOOP OF GOES IMAGES REVEALS
 VERY LITTLE CHANGE IN OVERALL CHARACTER OTHER THAN A SLIGHT
 REDUCTION IN UPPER LEVEL OUTFLOW TO THE NORTHEAST. CIMSS DATA FROM
 0000 UTC CONTINUES TO SHOW STRONG VERTICAL SHEAR...28 KTS
 WORTH...FROM THE WEST-SOUTHWEST. DVORAK INTENSITY ESTIMATES FROM
 PHFO...SAB AND JTWC ALL MAINTAIN NEKI AT 50 KT. ASCAT PASSES MISSED
 THE SYSTEM ENTIRELY SO THERE WAS NO HELP FROM THAT PLATFORM. WHILE
 CIMSS ADT GIVES AN INTENSITY OF 41 KT AT 0000 UTC...THE NOD WILL BE
 GIVEN TO THE SUBJECTIVE ESTIMATES BASED ON THE OVERALL SATELLITE
 PRESENTATION.  
 
 THERE HAS BEEN NO SIGNIFICANT CHANGE TO THE FORECAST RATIONALE FOR
 THIS CYCLE. NEKI IS MOVING IN A WEAK STEERING CURRENT WITH A WEAK
 MIDLEVEL RIDGE TO THE SOUTHEAST OVER THE MAIN HAWAIIAN ISLANDS AND
 A TROUGH FAR TO THE NORTH. A SIGNIFICANT SHORT WAVE TROUGH IS
 EXPECTED TO MOVE IN FROM THE WEST AND ABSORB NEKI. ALL OF THE MAIN
 DYNAMICAL MODELS AGREE WITH THIS GENERAL SCENARIO THOUGH DIFFER IN
 THE DETAILS. THE FORECAST CLOSELY FOLLOWS THE PREVIOUS FORECAST
 WITH SLIGHT ADJUSTMENTS IN SPEED AND IS ON THE EAST SIDE OF THE
 DYNAMICAL GUIDANCE ENVELOPE. IN ANY CASE...NEKI IS EXPECTED TO BE A
 NON-ENTITY AS A TROPICAL SYSTEM BY TUESDAY EVENING.
  
 NEKI IS MOVING OVER MARGINAL AND DECREASING SEA SURFACE
 TEMPERATURES. THIS ALONG WITH SIGNIFICANT LEVELS OF VERTICAL SHEAR
 SUPPORTS A WEAKENING TREND AS INDICATED BY THE MAIN INTENSITY
 OBJECTIVE AIDS. THUS...FORECAST CALLS FOR NEKI TO WEAKEN SLOWLY
 OVER THE NEXT COUPLE OF DAYS...FOLLOWED BY A TRANSITION TO AN
 EXTRATROPICAL STATE ON TUESDAY.
  
 THE LATEST BUOY DATA INDICATE IMPROVING WIND AND SEA CONDITIONS. 
 THEREFORE...THE TROPICAL STORM WARNING FOR THE PAPAHANAUMOKUAKEA
 NATIONAL MONUMENT WILL BE DISCONTINUED AS OF 500 PM HST.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      25/0300Z 25.3N 163.8W    50 KT
  12HR VT     25/1200Z 26.0N 163.7W    45 KT
  24HR VT     26/0000Z 27.2N 163.7W    45 KT
  36HR VT     26/1200Z 28.9N 163.7W    40 KT
  48HR VT     27/0000Z 31.7N 163.0W    40 KT...BECOMING EXTRATROPICAL
  72HR VT     28/0000Z 43.0N 156.5W    30 KT...EXTRATROPICAL
  
 $$
 FORECASTER KODAMA