838 
 WTNT45 KNHC 011503
 TCDAT5
 TROPICAL DEPRESSION TWENTY DISCUSSION NUMBER   1
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
 11 AM EDT SAT OCT 01 2005
  
 SATELLITE DATA AND SURROUNDING SURFACE OBSERVATIONS INDICATE THE
 LARGE LOW PRESSURE SYSTEM THAT HAS BEEN SLOWLY FESTERING OVER THE
 NORTHWESTERN CARIBBEAN SEA FOR THE PAST 4 DAYS HAS FINALLY
 ORGANIZED ENOUGH TO BE CLASSIFIED AS A TROPICAL CYCLONE. THE EXACT
 CENTER OF THE DEPRESSION IS DIFFICULT TO DETERMINE... BUT WIND AND
 PRESSURE REPORTS FROM NOAA BUOY 42056 SUGGEST THAT THE CENTER IS
 LOCATED JUST SOUTH OR SOUTHWEST OF THE BUOY LOCATION. THE INITIAL
 INTENSITY OF 25 KT IS BASED ON NOAA BUOY WIND REPORTS RANGING FROM
 23 TO 27 KT OVER THE PAST 9 HOURS. TWO SHIPS NEAR THE YUCATAN
 CHANNEL AT 01/06Z ALSO REPORTED SUSTAINED WINDS OF 28-32 KT.
 HOWEVER... QUALITY CONTROL CHECKS BY THE NOAA OCEAN PREDICTION
 CENTER INDICATE THAT THOSE WINDS WERE LIKELY 3-5 KT HIGH.
 CONVECTIVE BANDING FEATURES CONTINUE TO IMPROVE... AND SO HAS THE
 OUTFLOW PATTERN. AN AIR FORCE RESERVE AIRCRAFT IS ENROUTE TO
 INVESTIGATE THE SYSTEM AND SHOULD ARRIVE BY EARLY AFTERNOON.
  
 THE INITIAL MOTION ESTIMATE IS AN UNCERTAIN 295/05. THE LOW-LEVEL
 CIRCULATION CENTER HAS BEEN DIFFICULT TO LOCATE AT BEST... BUT THE
 SLOWLY BACKING WIND PROFILE AT NOAA BUOY 42056 SUGGESTS THAT THE
 CENTER IS SOMEWHERE NEARBY. THE AVAILABLE NHC MODEL GUIDANCE IS IN
 FAIR AGREEMENT ON THE CYCLONE MOVING WEST-NORTHWESTWARD FOR THE
 NEXT 72 HOURS AS THE BROAD BUT WEAK SUBTROPICAL RIDGE ALONG THE
 NORTHERN GULF COAST REMAINS INTACT THROUGH THE FORECAST PERIOD. THE
 FORECAST TRACK IS A BLEND OF THE 3 BAM MODELS... PLUS THE GFS AND
 UKMET SOLUTIONS.
 
 THE MAIN INHIBITING FACTOR FOR INTENSIFICATION DURING THE NEXT 4
 DAYS IS LAND INTERACTION. AS THE CYCLONE PASSES OVER THE YUCATAN
 PENINSULA IN 18-30 HOURS... INCREASED FRICTIONAL CONVERGENCE IS
 EXPECTED TO TIGHTEN UP THE RATHER LOOSE LOW-LEVEL WIND FIELD... AND
 THIS SHOULD AID IN THE QUICK REDEVELOPMENT OF DEEP CONVECTION ONCE
 THE SYSTEM EMERGES OVER THE SOUTHWESTERN GULF OF MEXICO BY 36
 HOURS. THE VERTICAL SHEAR IS FORECAST TO DECREASE TO 5 KT OR LESS
 WHILE THE CYCLONE IS OVER 29-30C SSTS. WITH A VERY FAVORABLE
 OUTFLOW PATTERN FORECAST BY ALL THE GLOBAL MODELS... THIS SYSTEM
 COULD EASILY REACH HURRICANE STRENGTH BEFORE IT MAKES A SECOND
 LANDFALL OVER NORTHEASTERN MEXICO. EXCLUDING LAND INTERACTION...
 THE SHIPS MODEL INCREASES THE INTENSITY TO 88 KT BY 96 HOURS.
  
 FORECASTER STEWART
 
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      01/1500Z 19.3N  85.8W    25 KT
  12HR VT     02/0000Z 19.9N  86.9W    35 KT
  24HR VT     02/1200Z 20.8N  88.8W    25 KT...INLAND YUCATAN
  36HR VT     03/0000Z 21.7N  90.7W    30 KT...OVER WATER
  48HR VT     03/1200Z 22.5N  92.5W    45 KT
  72HR VT     04/1200Z 23.4N  95.5W    60 KT
  96HR VT     05/1200Z 23.5N  98.5W    40 KT...INLAND NERN MEXICO
 120HR VT     06/1200Z 23.0N 101.5W    20 KT...DISSIPATING INLAND
  
  
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