000
WTPZ42 KNHC 120854
TCDEP2
 
TROPICAL DEPRESSION TWELVE-E DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP122011
200 AM PDT WED OCT 12 2011
 
THE AREA OF LOW PRESSURE JUST SOUTH OF THE GULF OF TEHUANTEPEC HAS
BECOME MUCH BETTER ORGANIZED OVER THE PAST FEW HOURS...WITH DEEP
CONVECTION INCREASING IN COVERAGE AND CURVATURE NEAR AND TO THE
WEST OF THE CENTER. AN ASCAT PASS AT AROUND 04Z SHOWED THE
CIRCULATION CENTER ON THE EAST SIDE OF THE CONVECTION AND THIS WAS
CONFIRMED BY SHIP OBSERVATIONS. BASED ON THIS...ADVISORIES ARE
INITIATED AT THIS TIME. THE DEPRESSION HAS LIMITED TIME TO
STRENGTHEN BEFORE IT MOVES INLAND...AND ONLY SLIGHT STRENGTHENING
IS SHOWN IN THE OFFICIAL FORECAST...WHICH BRINGS THE SYSTEM TO
MINIMAL TROPICAL STORM INTENSITY IN 12 HOURS. AFTER THAT TIME...THE
CYCLONE SHOULD WEAKEN...AND GLOBAL MODEL FIELDS SHOW THE LOW-LEVEL
CENTER LOSING DEFINITION BY 48 HOURS IN AN AREA OF BROAD CYCLONIC
FLOW THAT DEVELOPS FROM EASTERN MEXICO TO THE WESTERN CARIBBEAN
SEA. THE NHC FORECAST FOLLOWS THAT REASONING AND IS CLOSE TO THE
SHIPS AND LGEM. 

THE INITIAL MOTION ESTIMATE IS 360/4...AS THE DEPRESSION IS
CURRENTLY LOCATED TO THE WEST OF A MID-LEVEL RIDGE CENTERED OVER
THE WESTERN CARIBBEAN SEA. AS A DEEP-LAYER TROUGH MOVES INTO THE
GULF OF MEXICO...THE STEERING FLOW WILL VEER TO WESTERLY AND SHOULD
CAUSE THE CYCLONE TO TURN TOWARD THE NORTHEAST AND EAST OVER THE
NEXT DAY OR SO. THE NHC FORECAST IS CLOSE TO...BUT A LITTLE TO THE
LEFT OF THE GFS THROUGH DISSIPATION. 

THE MAIN THREAT FROM THIS SYSTEM WILL BE VERY HEAVY RAINFALL OVER
PORTIONS OF SOUTHEASTERN MEXICO AND GUATEMALA...EVEN AFTER THE
SYSTEM MOVES INLAND AND WEAKENS. 

 
FORECAST POSITIONS AND MAX WINDS
 
INIT  12/0900Z 14.7N  93.6W   30 KT  35 MPH
 12H  12/1800Z 15.2N  93.6W   35 KT  40 MPH
 24H  13/0600Z 15.7N  93.2W   35 KT  40 MPH...INLAND
 36H  13/1800Z 15.9N  91.9W   25 KT  30 MPH...INLAND
 48H  14/0600Z...DISSIPATED
 
$$
FORECASTER BRENNAN