769 
 WTNT41 KNHC 070305
 TCDAT1
 TROPICAL DEPRESSION SIXTEEN DISCUSSION NUMBER   3
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 11 PM EDT TUE SEP 06 2005
  
 DATA FROM THE WSR-88D AT MELBOURNE SHOWS THAT TROPICAL DEPRESSION
 SIXTEEN HAS A CIRCULATION CENTER ELONGATED WEST-SOUTHWEST TO
 EAST-NORTHEAST.  THE EARLIER NOAA AIRCRAFT FLIGHT FOUND MAXIMUM
 FLIGHT-LEVEL WINDS OF 27 KT MORE THAN 60 N MI AWAY FROM THE BROAD
 CENTER.  BASED ON A 27 KT WIND FROM BUOY 41010 AND SATELLITE
 INTENSITY ESTIMATES...THE INITIAL INTENSITY IS INCREASED TO 30 KT. 
 IT SHOULD BE NOTED THAT DURING THE LAST 30 MIN OR SO...THE
 MELBOURNE RADAR HINTS THAT A BETTER DEFINED INNER CORE MAY BE
 FORMING.  THE NEXT NOAA AIRCRAFT WILL ARRIVE IN THE CYCLONE AT
 ABOUT 06Z TO SEE IF THAT IS THE CASE.
 
 THE INITIAL MOTION IS AN UNCERTAIN 330/3...WITH THE RADAR DATA
 HINTING AT A FASTER FORWARD MOTION.  TRACK GUIDANCE AGREES ON A
 SLOW NORTHWESTWARD MOTION FOR 48 HR OR SO...THEN THERE IS SERIOUS
 DIVERGENCE.  THE GFDL...GFDN...ECMWF...AND BAMS TURN THE CYCLONE
 WESTWARD ACROSS THE FLORIDA PENINSULA INTO THE GULF OF MEXICO.  THE
 GFS...UKMET...NOGAPS...CANADIAN...AND BAMD TURN IT NORTHWARD AND
 EVEN NORTHEASTWARD OFFSHORE OF THE SOUTHEASTERN UNITED STATES.  THE
 MODELS ARE SIMILAR IN THE OVERALL PATTERN...WITH THE CYCLONE
 BETWEEN TWO SEGMENTS OF THE SUBTROPICAL RIDGE AS A STRONG
 DEEP-LAYER TROUGH MOVES OFF THE U.S. EAST COAST.  THE DIFFERENT
 TRACKS RESULT MAINLY FROM WHICH SEGMENT OF THE RIDGE WILL BE
 STRONGER...AND IT IS NOT APPARENT AT THIS TIME WHICH CLUSTER OF
 GUIDANCE WILL BE CORRECT.  THEREFORE...THE FORECAST TRACK WILL
 SPLIT THE DIFFERENCE BETWEEN THE TWO EXTREMES AND CALL FOR A SLOW
 NORTHWESTWARD MOTION AFTER 72 HR.  THIS IS A LOW-CONFIDENCE TRACK
 FORECAST.
 
 THE DEPRESSION IS EXPERIENCING SOME SOUTHERLY SHEAR WHICH IS
 PROBABLY SLOWING DEVELOPMENT.  THIS SHEAR WILL LIKELY LET UP IN
 12-24 HR AND ALLOW THE DEPRESSION TO STRENGTHEN INTO A TROPICAL
 STORM.  THE SHIPS MODEL AND THE SPREAD BETWEEN THE BAMS AND BAMD
 SUGGEST THAT THE SHEAR WILL INCREASE AGAIN IN 48-72 HR...SO THE
 INTENSITY FORECAST WILL CALL FOR A PEAK INTENSITY OF 60 KT AT THAT
 TIME.  THE INTENSITY FORECAST IS IN BEST AGREEMENT WITH THE SHIPS
 MODEL AND FAR ABOVE THE GFDL FORECAST.  THE GFS AND UKMET SUGGEST
 THAT THE DEEP-LAYER TROUGH COULD COME CLOSE ENOUGH TO FEED COOLER
 AIR INTO THE CYCLONE...AND SHOULD THAT HAPPEN IT COULD THROW A
 MONKEY WRENCH INTO THE CYCLONE STRUCTURE AND THE INTENSITY
 FORECAST.
  
 FORECASTER BEVEN
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      07/0300Z 27.4N  78.5W    30 KT
  12HR VT     07/1200Z 27.7N  78.8W    35 KT
  24HR VT     08/0000Z 28.1N  79.3W    40 KT
  36HR VT     08/1200Z 28.5N  79.7W    50 KT
  48HR VT     09/0000Z 28.8N  80.0W    60 KT
  72HR VT     10/0000Z 29.5N  80.5W    60 KT
  96HR VT     11/0000Z 30.5N  81.5W    50 KT...INLAND
 120HR VT     12/0000Z 30.5N  82.5W    30 KT...INLAND
  
  
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