427 
 WTPZ41 KNHC 292032
 TCDEP1
 TROPICAL STORM ALETTA DISCUSSION NUMBER  11
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP012006
 200 PM PDT MON MAY 29 2006
 
 THE LOW-LEVEL CENTER OF ALETTA BRIEFLY APPEARED EARLIER TODAY AS A
 BANDING FEATURE WAS TRYING TO DEVELOP EAST OF THE CENTER. HOWEVER...
 INFRARED IMAGERY INDICATES WARMING OF CLOUD TOPS AND THE CONVECTION
 IS VERY POORLY ORGANIZED. DVORAK CLASSIFICATIONS STILL SUPPORT
 TROPICAL STORM STRENGTH...AND ALTHOUGH THIS APPEARS TO BE GENEROUS
 THE INITIAL INTENSITY REMAINS AT 35 KT. 
  
 THE INITIAL MOTION FOR THIS ADVISORY IS 270/05. ALETTA HAS MAINTAINED
 A WESTWARD MOTION FOR MUCH OF THE DAY. THE GLOBAL MODELS CONTINUE TO
 BUILD A RIDGE TO THE NORTH AND WEST OF THE CYCLONE AND STEER ALETTA
 WESTWARD...HOWEVER MOST OF THE GLOBAL MODELS DISSIPATE THE CYCLONE
 WITHIN 72 HOURS. THE OFFICIAL TRACK FORECAST IS FASTER THAN THE
 PREVIOUS ADVISORY AND FOLLOWS THE BAMM IN THE EXTENDED PERIOD.
 
 ONLY A SMALL WINDOW EXISTS FOR ALETTA TO SLIGHTLY RE-STRENGTHEN AS
 THE GLOBAL MODELS FORECAST THE SHEAR TO DECREASE IN THE NEXT 12
 HOURS BEFORE INCREASING SHARPLY IN A DAY OR SO. ON THE OTHER
 HAND...IF THE CURRENT CONVECTIVE TREND CONTINUES...ALETTA MAY WEAKEN
 TO A TROPICAL DEPRESSION SOONER RATHER THAN LATER. THE INTENSITY
 FORECAST FAVORS THE GFDL GUIDANCE...WHEREAS THE SHIPS MODEL IS
 STRONGER BUT APPEARS UNREALISTIC DUE TO THE INCREASING SHEAR. AS A
 RESULT OF THE IMPINGING DRY AIR AND FORECASTED INCREASED SHEAR IN
 THE LATER PERIODS...THE CYCLONE IS LIKELY TO DISSIPATE TO A REMNANT
 LOW WITHIN 4-5 DAYS...IF NOT SOONER.
 
 FORECASTER MAINELLI/FRANKLIN
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      29/2100Z 15.9N 102.1W    35 KT
  12HR VT     30/0600Z 15.9N 102.8W    40 KT
  24HR VT     30/1800Z 15.8N 103.7W    40 KT
  36HR VT     31/0600Z 15.8N 104.7W    35 KT
  48HR VT     31/1800Z 15.6N 105.7W    35 KT
  72HR VT     01/1800Z 15.5N 107.5W    30 KT
  96HR VT     02/1800Z 15.5N 109.0W    25 KT
 120HR VT     03/1800Z 15.5N 111.0W    25 KT...REMNANT LOW
  
  
 $$