333 
 WTPZ42 KNHC 151447
 TCDEP2
 TROPICAL DEPRESSION GREG DISCUSSION NUMBER  18
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 8 AM PDT MON AUG 15 2005
  
 GOES SHORTWAVE INFRARED IMAGERY CONTINUES TO REVEAL AN EXPOSED LOW-
 LEVEL CIRCULATION WITH THE NEAREST CONVECTION ABOUT 40-45 NM
 SOUTHWEST OF THE LOW LEVEL CENTER. EASTERLY SHEAR MAINTAINS ITS
 GRIP ON THE SYSTEM. DVORAK INTENSITY ESTIMATES REMAIN
 30 KT...AS DOES THE ADVISORY INTENSITY. DUE TO THE CURRENT
 DISORGANIZATION OF THE DEPRESSION...AND SINCE THE SHEAR IS NOT
 FORECAST TO RELAX...NO INTENSITY CHANGE IS INDICATED...DESPITE THE
 AGGRESSIVE GFDL AND OPTIMISTIC SHIPS FORECASTS. 
  
 THE MOTION OVER THE PAST 6 HOURS HAS OSCILLATED BETWEEN SOUTHWEST
 AND WEST-SOUTHWEST WITH A MEAN INITIAL MOTION OF 245/4. THE
 FORECAST SOLUTIONS FROM THE VARIOUS DYNAMICAL MODELS ARE IN BETTER
 AGREEMENT AT LEAST THROUGH 72 HOURS AND ARE UNANIMOUS IN
 FORECASTING A GENERAL WESTWARD TREND. THE MODELS DIVERGE
 SIGNIFICANTLY AFTER 72 HOURS WITH THE NOGAPS/UKMET AND THE
 GUNS...GUNA AND CONU DYNAMICAL CONCENSUS FORECASTING A TURN TOWARD
 THE NORTHWEST. ONCE AGAIN THE GFDL FORECASTS A SLOW WEST-
 SOUTHWESTWARD DRIFT AS A STRENGTHENING TROPICAL STORM FOR THE
 NEXT THREE DAYS...FOLLOWED BY AN ABRUPT TURN TO THE NORTH-NORTHEAST.
 THE GFS IS FORECASTING A FAIRLY SIGNIFICANT MID LEVEL CIRCULATION
 SOUTH OF BAJA CALIFORNIA...WHICH IS LIKELY DUE TO POOR
 INITIALIZATION.  THEREFORE THAT MODEL'S TRACK...WHICH MOVES GREG IN
 A CLOCKWISE LOOP...DOES NOT APPEAR TO BE REALISTIC. THE OFFICIAL
 FORECAST IS SIMILAR TO THE PREVIOUS AND INDICATES A VERY SLOW
 WESTWARD MOTION AT ABOUT 5 KNOTS THROUGHOUT THE FORECAST PERIOD.
  
 FORECASTER COBB/PASCH 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      15/1500Z 14.0N 116.4W    30 KT
  12HR VT     16/0000Z 13.7N 117.0W    30 KT
  24HR VT     16/1200Z 13.4N 117.7W    30 KT
  36HR VT     17/0000Z 13.1N 118.6W    30 KT
  48HR VT     17/1200Z 12.7N 120.0W    30 KT
  72HR VT     18/1200Z 12.5N 122.0W    30 KT
  96HR VT     19/1200Z 12.5N 124.0W    30 KT
 120HR VT     20/1200Z 12.5N 126.0W    30 KT
  
 $$
 

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