751 
 WTNT44 KNHC 280257
 TCDAT4
 TROPICAL DEPRESSION NINE DISCUSSION NUMBER   2
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL092006
 1100 PM EDT WED SEP 27 2006
  
 ALTHOUGH THE DEPRESSION IS NOT VERY IMPRESSIVE IN CONVENTIONAL
 SATELLITE IMAGERY... MICROWAVE OVERPASSES BY QUIKSCAT AT 2132 UTC
 AND SSMIS AT 2309 UTC SUGGEST THAT IT IS NEARING TROPICAL STORM
 STRENGTH.  LATEST DVORAK INTENSITY ESTIMATES...HOWEVER...REMAIN 30
 KT FROM ALL AGENCIES AND THIS WILL BE THE ADVISORY INTENSITY.  THE
 CENTER OF THE DEPRESSION IS LOCATED JUST SOUTH OF THE PRIMARY AREA
 OF DEEP CONVECTION DUE TO SOUTHERLY WIND SHEAR IMPOSED BY AN
 UPPER-LEVEL LOW TO THE WEST OF THE DEPRESSION.  MOST OF THE GLOBAL
 MODELS GRADUALLY WEAKEN THIS FEATURE AND THEREFORE THE SHEAR OVER
 THE NEXT DAY OR TWO.  THE OFFICIAL FORECAST CALLS FOR GRADUAL
 STRENGTHENING DURING THE NEXT 48 HOURS.  THEREAFTER...SOUTHWESTERLY
 SHEAR IS EXPECTED TO INCREASE AGAIN WHILE SSTS COOL...WHICH SHOULD
 INHIBIT FURTHER STRENGTHENING.  THE NEW OFFICIAL INTENSITY FORECAST
 IS CLOSE TO THE SHIPS AND GFDL INTENSITY GUIDANCE...AND SIMILAR TO
 THE PREVIOUS ADVISORY.
 
 THE INITIAL MOTION ESTIMATE IS 315/11.  GLOBAL MODEL GUIDANCE
 INDICATES THAT THE DEPRESSION WILL BE STEERED AROUND THE WESTERN
 PERIPHERY OF A MID-TROPOSPHERIC RIDGE LOCATED TO THE NORTHEAST OF
 THE CYCLONE.  IN ABOUT 48 HOURS...A LARGE DEEP LAYERED TROUGH IS
 PREDICTED TO BE DEPARTING THE EAST COAST OF THE UNITED STATES. 
 THIS SHOULD ALLOW THE TROPICAL CYCLONE TO TURN NORTHWARD...THEN
 NORTHEASTWARD AHEAD OF THIS TROUGH.  THE GFS IS ON THE WESTERN EDGE
 OF THE MODEL GUIDANCE AS IT DEPICTS A MUCH WEAKER AND MORE SHALLOW
 SYSTEM THAN ANTICIPATED BY THE SHIPS AND GFDL.  SINCE THE SHIPS AND
 GFDL ARE IN SUCH GOOD AGREEMENT ON THE FUTURE INTENSITY OF THE
 SYSTEM...THE GFDL TRACK MIGHT BE A MORE LIKELY SOLUTION.  THE
 OFFICIAL FORECAST IS ADJUSTED WESTWARD AND SLOWER COMPARED TO THE
 PREVIOUS ADVISORY TO BE IN BETTER AGREEMENT WITH THE GFDL TRACK.
  
 INITIAL      28/0300Z 27.2N  53.8W    30 KT
  12HR VT     28/1200Z 28.2N  55.0W    35 KT
  24HR VT     29/0000Z 29.9N  56.5W    40 KT
  36HR VT     29/1200Z 31.6N  57.6W    45 KT
  48HR VT     30/0000Z 33.6N  58.1W    50 KT
  72HR VT     01/0000Z 38.0N  57.0W    50 KT
  96HR VT     02/0000Z 42.0N  52.5W    50 KT...EXTRATROPICAL
 120HR VT     03/0000Z 46.0N  45.0W    50 KT...EXTRATROPICAL
  
 $$
 FORECASTER BROWN/KNABB