000
WTPZ44 KNHC 291445
TCDEP4
TROPICAL DEPRESSION FOURTEEN-E DISCUSSION NUMBER   1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP142009
800 AM PDT SAT AUG 29 2009
 
SATELLITE IMAGERY INDICATES THAT THE DISTURBANCE LOCATED ABOUT 1000
MILES SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA HAS BECOME
BETTER ORGANIZED...WITH A LARGE AREA OF COLD CLOUD TOPS NEAR AND TO
THE SOUTHWEST OF THE ESTIMATED CENTER LOCATION. DVORAK CI-NUMBERS
AT 1200 UTC FROM TAFB AND SAB WERE A CONSENSUS 2.0...THEREFORE
ADVISORIES ARE INITIATED AT THIS TIME AND THE INITIAL INTENSITY IS
SET TO 30 KT. 

THE INITIAL MOTION ESTIMATE IS 315/08...AS THE DEPRESSION IS BEING
STEERED BY A WEAKNESS IN THE MID-LEVEL SUBTROPICAL RIDGE TO ITS
NORTH. THERE IS LARGE SPREAD IN THE TRACK MODEL GUIDANCE...WITH TWO
SCENARIOS DEPICTED. THE FIRST IS SHOWN BY THE GFS...NOGAPS...UKMET
AND GFDL...WHICH SHOW A TURN TO THE NORTHEAST...SEEMINGLY DUE TO
INTERACTION WITH THE STRONGER HURRICANE JIMENA. THE GFS...NOGAPS AND
GFDL SHOW THIS NORTHEASTWARD MOTION BY 36 HOURS...WHILE THE UKMET
DOES NOT SHOW IT UNTIL LATER IN THE PERIOD. THE SECOND SCENARIO IS
SHOWN BY THE HWRF...CANADIAN...ECMWF...AND THE BAMS...WHICH SHOW A
TURN TOWARD THE NORTH OR NORTH-NORTHEAST INTO THE BREAK IN THE
SUBTROPICAL RIDGE...FOLLOWED BY A WESTWARD TURN LATE IN THE PERIOD.
FOR NOW THE OFFICIAL FORECAST LEANS TOWARD THE SECOND SCENARIO...
ASSUMING THAT THERE WILL NOT BE SUBSTANTIAL INTERACTION WITH
JIMENA. THE FORECAST SPEED IS KEPT SLOW THROUGH THE PERIOD DUE TO
THE HIGH DEGREE OF UNCERTAINTY. THE OFFICIAL TRACK SHOWS A TURN
TOWARD THE NORTH BY 36 HOURS AND A SLOW NORTHWARD MOTION THROUGH
DAY 3...FOLLOWED BY A GRADUAL TURN TOWARD THE WEST-NORTHWEST AND
WEST AT THE END OF THE PERIOD.

DESPITE THE DEPRESSION BEING OVER WARM WATERS AND IN A LOW SHEAR
ENVIRONMENT...THE INTENSITY GUIDANCE ONLY SHOWS LIMITED
STRENGTHENING. THIS MAY BE BECAUSE THE SHIPS MODEL SHOWS THE
CYCLONE MOVING INTO A PROGRESSIVELY LESS FAVORABLE THERMODYNAMIC
ENVIRONMENT THROUGH THE PERIOD. THE OFFICIAL FORECAST IS CLOSEST TO
THE SHIPS AND LGEM THROUGH THE FIRST 3 DAYS...AND THEN SHOWS A
LITTLE MORE WEAKENING AT DAYS 4 AND 5 SINCE THE DEPRESSION WILL BE
MOVING INTO COOLER WATERS AS IT APPROACHES 20N ON THE OFFICIAL
FORECAST TRACK. 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      29/1500Z 13.3N 121.5W    30 KT
 12HR VT     30/0000Z 14.0N 122.3W    35 KT
 24HR VT     30/1200Z 14.9N 122.7W    40 KT
 36HR VT     31/0000Z 15.8N 122.7W    45 KT
 48HR VT     31/1200Z 16.9N 122.7W    40 KT
 72HR VT     01/1200Z 18.5N 123.0W    40 KT
 96HR VT     02/1200Z 19.5N 125.0W    35 KT
120HR VT     03/1200Z 20.0N 127.0W    30 KT
 
$$
FORECASTER BRENNAN