637 
 WTPZ41 KNHC 302031
 TCDEP1
 TROPICAL DEPRESSION ELEVEN-E DISCUSSION NUMBER   1
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 2 PM PDT MON AUG 30 2004
  
 VISIBLE AND INFRARED SATELLITE IMAGERY INDICATES THAT THE TROPICAL
 DISTURBANCE SOUTHWEST OF ACAPULCO HAS BECOME ORGANIZED ENOUGH TO BE
 CLASSIFIED AS A TROPICAL DEPRESSION. CURRENT SATELLITE INTENSITY
 ESTIMATES REFLECT THIS WITH A CONSENSUS 2.0 FROM TAFB AND SAB. AFWA
 CLASSIFIED THE SYSTEM WITH A 1.5 BASED ON THE PATTERN T...BUT THE
 DATA T NUMBER WAS ALSO A 2.0. IN ADDITION...QUIKSCAT AMBIGUITY DATA
 AND MICROWAVE IMAGERY PROVIDE ENOUGH SUPPORT FOR A SURFACE
 CIRCULATION BOUNDED BY CONVECTION PRIMARILY OVER THE WESTERN
 SEMICIRCLE. THE DEPRESSION BEGINS WITH AN INITIAL INTENSITY OF 30
 KT.
 
 INITIAL MOTION IS AN UNCERTAIN 300/6. THE DEPRESSION IS MOVING
 SLOWLY TO THE WEST-NORTHWEST ON THE SOUTHERN PERIPHERY OF A WEAK
 MID-LEVEL RIDGE WHICH EXTENDS ACROSS MEXICO AND IS ANCHORED BY AN
 ANTICYCLONE OVER SOUTHERN CALIFORNIA. THIS GENERAL MOTION IS
 EXPECTED OVER THE FIRST 48 HOURS BUT AN ACCELERATION IS ANTICIPATED
 THEREAFTER AS THE SYSTEM BECOMES MORE UNDER THE INFLUENCE OF THE
 RIDGE AND IS STEERED BY STRONGER DEEP-LAYERED FLOW. IN THE 4 TO 5
 DAY RANGE...A LONGWAVE TROUGH IS EXPECTED TO MOVE ACROSS THE
 WESTERN UNITED STATES. THIS MAY PROVIDE JUST ENOUGH WEAKNESS IN THE
 RIDGE TO ALLOW FOR A SLOWER AND POTENTIALLY MORE NORTHWARD
 MOTION...BUT THIS IS VERY RELIANT ON THE STRENGTH OF THE SYSTEM AT
 THAT TIME. THE NOGAPS FAVORS A STRONG TROUGH AND THE UKMET FAVORS A
 SHALLOW TROUGH. THE OFFICIAL FORECAST FOLLOWS THE GFS SOLUTION
 WHICH IS A COMPROMISE OF THE NOGAPS AND UKMET.
 
 THE OFFICIAL INTENSITY FORECAST GRADUALLY STRENGTHENS THE DEPRESSION
 TO 60 KT BY 72 HOURS. THE SYSTEM WILL BEGIN MOVING OVER WATER
 TEMPERATURES BELOW 26C AFTER 72 HOURS SO SLIGHT WEAKENING IS
 ANTICIPATED THEREAFTER. VERTICAL SHEAR IS EXPECTED TO BE MARGINAL
 THROUGH THE FORECAST PERIOD AND THIS SHOULD PLAY A CRITICAL PART IN
 HOW STRONG THE SYSTEM WILL ULTIMATELY BECOME.
  
 FORECASTER BERG/PASCH
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      30/2100Z 12.5N 103.9W    30 KT
  12HR VT     31/0600Z 13.0N 104.9W    35 KT
  24HR VT     31/1800Z 13.9N 106.8W    40 KT
  36HR VT     01/0600Z 14.8N 108.7W    45 KT
  48HR VT     01/1800Z 16.0N 111.0W    50 KT
  72HR VT     02/1800Z 18.5N 115.5W    60 KT
  96HR VT     03/1800Z 20.5N 119.5W    60 KT
 120HR VT     04/1800Z 22.0N 123.0W    50 KT
  
 $$