151 
 WTPZ44 KNHC 020244
 TCDEP4
 TROPICAL DEPRESSION FOUR-E DISCUSSION NUMBER   1
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP042008
 800 PM PDT TUE JUL 01 2008
  
 ASCAT DATA AT AROUND 16Z SHOWED THAT THE LOW PRESSURE AREA SOUTHWEST
 OF MANZANILLO MEXICO HAD A BROAD CENTER ELONGATED NORTH-NORTHWEST
 TO SOUTH-SOUTHEAST.  SINCE THAT TIME...SATELLITE IMAGERY INDICATES
 THAT THE CIRCULATION AND ASSOCIATED SHOWER ACTIVITY HAS SOMEWHAT
 CONSOLIDATED AT THE SOUTHERN END OF THE ELONGATION.  BASED ON
 THIS...ADVISORIES ARE INITIATED ON TROPICAL DEPRESSION FOUR-E.  THE
 INITIAL INTENSITY IS 30 KT IN AGREEMENT WITH SATELLITE INTENSITY
 ESTIMATES FROM TAFB AND SAB...AS WELL AS THE OBSERVED WINDS IN THE
 EARLIER ASCAT DATA.
 
 THE INITIAL MOTION IS 315/6.  THE DEPRESSION IS ON THE SOUTHWEST
 SIDE OF A WEAK MID-LEVEL RIDGE EXTENDING FROM THE SOUTHWESTERN
 UNITED STATES INTO MEXICO.  THE LARGE-SCALE MODELS FORECAST THE
 RIDGE TO WEAKEN DURING THE NEXT 48-72 HR...WHICH RESULTS IN WEAK
 STEERING CURRENTS.  THE ECMWF AND THE NOGAPS...WHICH KEEP THE
 CYCLONE ALIVE FOR 5 DAYS...FORECAST A SLOW NORTHWESTWARD MOTION FOR
 48-72 HR AND A SLOW WESTWARD MOTION THEREAFTER.  THIS IS SUPPORTED
 BY THE UKMET AND GFS UNTIL THEIR MODEL CYCLONES DISSIPATE NEAR 96
 HR.  THE FORECAST TRACK FOLLOWS THIS SCENARIO IN BEST AGREEMENT
 WITH THE ECMWF.  THERE IS A CHANCE OF ERRATIC MOTION DURING THE
 FIRST 24 HR AS THE CYCLONE CONSOLIDATES.
 
 THE DEPRESSION IS CURRENTLY UNDER A LARGE UPPER-LEVEL ANTICYCLONE
 WITH WITH FAIR TO GOOD CIRRUS OUTFLOW IN ALL DIRECTIONS.  THIS
 SHOULD ALLOW GRADUAL STRENGTHENING UNTIL THE CYCLONE REACHES COOLER
 SEA SURFACE TEMPERATURES IN 36-48 HR.  THE GFS...ECMWF...AND NOGAPS
 FORECAST INCREASED VERTICAL WIND SHEAR AFTER 72-96 HR.  SHOULD THIS
 VERIFY...THE SYSTEM COULD WEAKEN FASTER THAN CURRENTLY FORECAST.
 
 THE ASCAT DATA SHOWED 25-30 KT WINDS IN A BAND THAT IS CURRENTLY
 ABOUT 200 N MI FROM THE CENTER IN THE NORTHEASTERN QUADRANT.  WHILE
 THE CENTER OF THE CYCLONE IS EXPECTED TO REMAIN WELL OFFSHORE...
 INTERESTS ALONG THE WEST COAST OF MEXICO FROM ZIHUATANEJO TO PUERTO
 VALLARTA SHOULD MONITOR ITS PROGRESS IN CASE IT COMES CLOSER THAN
 CURRENTLY FORECAST OR THE WIND FIELD IS LARGER THAN FORECAST. 
 RAINBANDS ASSOCIATED WITH THE SYSTEM COULD AFFECT PORTIONS OF THE
 WESTERN COAST OF MEXICO TONIGHT AND WEDNESDAY.
   
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      02/0300Z 15.9N 107.0W    30 KT
  12HR VT     02/1200Z 16.4N 107.7W    35 KT
  24HR VT     03/0000Z 17.0N 108.5W    40 KT
  36HR VT     03/1200Z 17.5N 109.0W    45 KT
  48HR VT     04/0000Z 18.0N 109.5W    40 KT
  72HR VT     05/0000Z 19.0N 110.5W    35 KT
  96HR VT     06/0000Z 19.5N 112.0W    30 KT
 120HR VT     07/0000Z 19.5N 113.5W    25 KT
  
 $$
 FORECASTER BEVEN