540 
 WTPZ43 KNHC 220833
 TCDEP3
  
 TROPICAL DEPRESSION THIRTEEN-E DISCUSSION NUMBER   2
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP132012
 200 AM PDT SAT SEP 22 2012
  
 CONVENTIONAL SATELLITE IMAGERY AND MICROWAVE DATA INDICATE THAT THE
 CLOUD PATTERN IS GRADUALLY BECOMING BETTER ORGANIZED. THE
 CONVECTION IS RAGGED NEAR THE CENTER...BUT THERE ARE BANDING
 FEATURES DEVELOPING IN ALL QUADRANTS. THE OUTFLOW IS FAIR
 INDICATING THAT THE SHEAR IS LOW. IN FACT...SHIPS MODEL MAINTAINS
 VERY LOW SHEAR THROUGH 5 DAYS. THE INITIAL INTENSITY IS KEPT AT 30
 KNOTS BASED ON THE AVERAGE OF DVORAK T-NUMBERS. DUE TO THE LOW
 SHEAR ENVIRONMENT AND THE WARM OCEAN...STRENGTHENING IS FORECAST.
 BY THE END OF THE FORECAST PERIOD...THE CIRCULATION WILL BE NEARING
 COOL WATERS AND A GRADUAL WEAKENING SHOULD THEN BEGIN. 
 
 THE INITIAL MOTION IS A LITTLE BIT UNCERTAIN SINCE THE CENTER IS
 STILL IN FORMATIVE STAGE. THE BEST ESTIMATE IS 280 DEGREES AT 6
 KNOTS. THE DEPRESSION IS SOUTH OF A SUBTROPICAL RIDGE CENTERED
 ACROSS NORTHERN MEXICO AND THE SOUTHWESTERN UNITED STATES. THE FLOW
 AROUND THE RIDGE WILL STEER THE CYCLONE ON A GENERAL WEST-NORTHWEST
 TO NORTHWEST TRACK FOR THE NEXT 3 DAYS. AFTER THAT...AN EASTWARD
 MOVING SHORTWAVE WILL ERODE THE RIDGE...AND THE CYCLONE SHOULD TURN
 MORE THE NORTH WITH A DECREASE IN FORWARD SPEED. THE NHC FORECAST
 HAS BEEN SHIFTED A LITTLE BIT TO THE NORTH AND EAST FROM THE
 PREVIOUS ONE. THIS IS BASED ON THE FACT THAT BOTH THE GFS AND THE
 ECMWF GLOBAL MODELS...AND THE HWRF/GFDL PAIR...TURN THE CYCLONE
 NORTHWARD AHEAD OF THE APPROACHING TROUGH. THE BULK OF THE
 DYNAMICAL MODELS RECURVE THE CYCLONE EAST OF 118 DEGREES WEST.     
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  22/0900Z 13.7N 107.5W   30 KT  35 MPH
  12H  22/1800Z 14.0N 108.4W   40 KT  45 MPH
  24H  23/0600Z 14.5N 109.7W   50 KT  60 MPH
  36H  23/1800Z 15.5N 111.0W   60 KT  70 MPH
  48H  24/0600Z 16.3N 112.5W   70 KT  80 MPH
  72H  25/0600Z 18.0N 115.5W   75 KT  85 MPH
  96H  26/0600Z 19.5N 117.0W   65 KT  75 MPH
 120H  27/0600Z 21.0N 118.0W   50 KT  60 MPH
  
 $$
 FORECASTER AVILA