522 
 WTPZ45 KNHC 271435
 TCDEP5
 TROPICAL STORM GEORGETTE DISCUSSION NUMBER   5
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 8 AM PDT FRI AUG 27 2004
  
 A 0902Z AQUA OVERPASS SHOWS THAT THE CENTER OF GEORGETTE REMAINS
 EXPOSED TO THE NORTHEAST OF THE PRIMARY CONVECTION...AS ANALYSES
 FROM CIMSS AT THE UNIVERSITY OF WISCONSIN CONTINUES TO INDICATE
 15-20 KT OF EASTERLY TO NORTHEASTERLY VERTICAL SHEAR.  THE
 CONVECTION CONTINUES QUITE STRONG...WITH TOPS TO -88C.  SATELLITE
 INTENSITY ESTIMATES ARE 55 KT FROM TAFB AND SAB...AND 45 KT FROM
 AFWA.  BASED ON THIS AND THE EXPOSED CENTER...THE INITIAL INTENSITY
 REMAINS 50 KT.
 
 THE INITIAL MOTION IS 300/15.  GEORGETTE REMAINS ON THE SOUTH SIDE
 OF A SUBTROPICAL RIDGE...WHICH LARGE-SCALE MODELS FORECAST TO
 PERSIST THROUGH 96 HR.  AFTER THAT...A MID/UPPER-LEVEL TROUGH
 DIGGING SOUTHWARD NEAR 135W MAY WEAKEN THE RIDGE SOMEWHAT.  THE
 OVERALL PATTERN SHOULD CAUSE GEORGETTE TO TURN WETSWARD DURING THE
 FIRST 96 HR...AND THE OFFICIAL FORECAST FOLLOWS THIS SCENARIO. 
 AFTER 96 HR...THE NOGAPS AND THE BAM MODELS INDICATE THE
 POSSIBILITY OF A WEST-NORTHWESTWARD MOTION.  FOR NOW...THE OFFICIAL
 FORECAST CALLS FOR A CONTINUED WESTWARD MOTION ON THE BASIS THAT A
 WEAKENING GEORGETTE WILL BE STEERED MORE BY THE LOW-LEVEL FLOW. 
 THE NEW FORECAST TRACK IS NUDGED A LITTLE TO THE NORTH OF THE
 PREVIOUS TRACK AND IS IN BEST AGREEMENT WITH THE GFDL.
 
 THE DYNAMICAL MODELS SUGGEST THE SHEAR SHOULD DECREASE DURING THE
 NEXT 24 HR...WHICH LEAVES GEORGETTE A WINDOW OF OPPORTUNITY TO
 BECOME A HURRICANE BEFORE REACHING COLDER SEA SURFACE TEMPERATURES. 
 THE FORECAST TRACK TAKES THE STORM FROM THE 29C SSTS IT IS
 CURRENTLY OVER TO 26C IN ABOUT 24 HR AND COLDER THAN 25C AFTER 48
 HR.  BASED ON THIS AND THE FORECAST DECREASE IN SHEAR...THE
 INTENSITY FORECAST CALLS FOR GEORGETTE TO BECOME A HURRICANE AT
 ABOUT 24 HR AND THEN SLOWLY WEAKEN THEREAFTER IN BEST AGREEMENT
 WITH THE GFDL.
  
 FORECASTER BEVEN
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      27/1500Z 18.4N 111.9W    50 KT
  12HR VT     28/0000Z 19.2N 113.9W    60 KT
  24HR VT     28/1200Z 19.9N 116.4W    65 KT
  36HR VT     29/0000Z 20.2N 118.7W    65 KT
  48HR VT     29/1200Z 20.4N 120.9W    60 KT
  72HR VT     30/1200Z 20.5N 125.0W    50 KT
  96HR VT     31/1200Z 20.5N 129.5W    35 KT
 120HR VT     01/1200Z 20.5N 134.0W    25 KT
  
  
 $$