646 
 WTNT45 KNHC 031435
 TCDAT5
 TROPICAL STORM ZETA DISCUSSION NUMBER  17
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 10 AM EST TUE JAN 03 2006
  
 ZETA'S CENTER APPEARS TO BE PARTIALLY EMBEDDED IN THE CENTRAL DENSE
 OVERCAST AND DVORAK T-NUMBERS FROM TAFB AND SAB ARE 3.5...
 CORRESPONDING TO A 55-KT CURRENT INTENSITY ESTIMATE.  AN SSMIS
 IMAGE AT 1116Z DEPICTED AN EYE-LIKE RING...ALTHOUGH THIS FEATURE
 APPEARED TO BE AT MID-LEVELS AND DISPLACED NORTHEAST OF THE
 LOW-LEVEL CENTER.  UPPER-LEVEL OUTFLOW IS FAIRLY WELL DEFINED OVER
 THE NORTHERN SEMICIRCLE OF THE STORM...AND SO FAR THE STRONG WINDS
 IN THE UPPER-TROPOSPHERIC ENVIRONMENT HAVE NOT HAD MUCH OF A
 DISRUPTIVE INFLUENCE.  AN UPPER-LEVEL TROUGH...THAT IS CURRENTLY
 NEARING ZETA...IS PREDICTED BY THE GLOBAL MODELS TO SPLIT AND THIS
 COULD BRIEFLY CREATE A MORE FAVORABLE ENVIRONMENT FOR STRENGTHENING
 TODAY.  THE OFFICIAL FORECAST WILL SHOW NO WEAKENING UNTIL A LITTLE
 LATER IN THE PERIOD...WHEN STRONG UPPER-LEVEL NORTHWESTERLIES IN
 THE WAKE OF THE TROUGH ARE EXPECTED TO BEGIN TAKING THEIR TOLL ON
 ZETA.
 
 EVEN WITH VISIBLE IMAGES...THE CENTER LOCATION IS NOT THAT OBVIOUS
 AND THE INITIAL MOTION ESTIMATE IS A SOMEWHAT UNCERTAIN 250/4.  A
 MAINLY WESTWARD TRACK...TO THE SOUTH OF A LOW-LEVEL RIDGE...IS
 LIKELY FOR THE NEXT DAY OR SO.  THEREAFTER A LARGE LOW MOVING FROM
 THE WESTERN ATLANTIC IS FORECAST TO TURN ZETA TO THE RIGHT.  THE
 OFFICIAL FORECAST FOLLOWS THIS REASONING AND IS TO THE RIGHT OF THE
 MODEL CONSENSUS AND LEANS TOWARD THE GFDL TRACK.
  
 FORECASTER PASCH
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      03/1500Z 23.0N  42.1W    55 KT
  12HR VT     04/0000Z 23.0N  42.7W    55 KT
  24HR VT     04/1200Z 23.0N  43.8W    55 KT
  36HR VT     05/0000Z 23.4N  44.8W    45 KT
  48HR VT     05/1200Z 24.5N  45.5W    40 KT
  72HR VT     06/1200Z 27.5N  46.5W    30 KT
  96HR VT     07/1200Z 30.0N  46.5W    25 KT...REMNANT LOW
 120HR VT     08/1200Z...DISSIPATED
  
  
 $$