000
WTPZ44 KNHC 100240
TCDEP4
TROPICAL DEPRESSION NINE-E DISCUSSION NUMBER   2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP092009
800 PM PDT SUN AUG 09 2009

SATELLITE IMAGERY INDICATES THAT THE OVERALL ORGANIZATION OF THE
DEPRESSION HAS CHANGED LITTLE THIS EVENING.  MOST OF THE CONVECTIVE
BANDING SEEN EARLY TODAY HAS DISSIPATED...WHILE A SOMEWHAT SHAPELESS
AREA OF CONVECTION HAS DEVELOPED NEAR AND TO THE EAST OF THE
CENTER.  

LATE AFTERNOON VISIBLE SATELLITE IMAGERY AND MICROWAVE DATA SUGGEST
THAT THE CENTER OF THE DEPRESSION IS A LITTLE FURTHER NORTH AND
WEST THAN PREVIOUSLY ESTIMATED.  THE SOMEWHAT UNCERTAIN INITIAL
MOTION ESTIMATE IS 285/8 KT.  THE DEPRESSION IS CURRENTLY SOUTH OF
A MID-LEVEL RIDGE THAT EXTENDS WEST-SOUTHWESTWARD FROM NORTHERN
MEXICO INTO THE EASTERN PACIFIC.  THE RIDGE IS FORECAST TO BUILD
WESTWARD DURING THE FORECAST PERIOD WHICH SHOULD KEEP THE CYCLONE
ON A GENERAL WEST-NORTHWESTWARD HEADING.  THE MODELS ARE IN GOOD
AGREEMENT ON THIS MOTION...HOWEVER AT VARYING FORWARD SPEEDS.  THE
NHC TRACK IS CLOSE TO THE MODEL CONSENSUS THROUGH 72 HOURS...BUT IS
A LITTLE SLOWER THAN THE PREVIOUS ADVISORY AT DAYS 4 AND 5.

WATER VAPOR IMAGERY INDICATES THAT THE DEPRESSION IS MOVING INTO AN
AREA OF UPPER-LEVEL WESTERLY WINDS.  THE SHIPS MODEL AND A
UW-CIMSS SHEAR ANALYSIS CURRENTLY DIAGNOSE ABOUT 15 KT OF SHEAR OVER
THE CYCLONE.  THE DYNAMICAL MODELS PREDICT THAT MODERATE WEST TO
WEST-NORTHWESTERLY UPPER-LEVEL WINDS CONTINUE ALONG THE PATH OF THE
DEPRESSION DURING THE NEXT 2-3 DAYS.  BECAUSE OF THIS...MOST OF THE
INTENSITY GUIDANCE ONLY SHOWS MODEST STRENGTHENING AND SO DOES THE
OFFICIAL FORECAST.  BEYOND 72 HOURS...ALTHOUGH THE SHEAR IS
FORECAST TO DECREASE...THE CYCLONE IS EXPECTED TO BE MOVING OVER
COOLER WATERS...WHICH SHOULD INDUCE WEAKENING.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      10/0300Z 14.8N 121.5W    30 KT
 12HR VT     10/1200Z 15.0N 122.7W    35 KT
 24HR VT     11/0000Z 15.4N 124.4W    40 KT
 36HR VT     11/1200Z 15.8N 126.1W    40 KT
 48HR VT     12/0000Z 16.2N 128.0W    45 KT
 72HR VT     13/0000Z 16.9N 131.7W    50 KT
 96HR VT     14/0000Z 17.0N 135.5W    45 KT
120HR VT     15/0000Z 17.0N 139.5W    40 KT
 
$$
FORECASTER BROWN