000
WTPZ42 KNHC 011453
TCDEP2
TROPICAL STORM BARBARA DISCUSSION NUMBER  12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP022007
800 AM PDT FRI JUN 01 2007
 
THE CLOUD PATTERN ASSOCIATED WITH BARBARA HAS BECOME BETTER
DEFINED THIS MORNING AS CONVECTIVE BANDING FEATURES HAVE DEVELOPED.
A 1220 UTC QUIKSCAT OVERPASS LEAVES LITTLE DOUBT THAT A WELL-DEFINED
SURFACE CIRCULATION EXISTS AND IN FACT...IT INDICATES THAT BARBARA
IS ONCE AGAIN A TROPICAL STORM.
 
THE INITIAL MOTION ESTIMATE IS 085/4. BECAUSE THE CYCLONE IS
BECOMING A DEEP SYSTEM AGAIN...THE FLOW AHEAD OF THE TROUGH OVER
THE GULF OF MEXICO WILL LIKELY STEER THE CYCLONE NORTHEASTWARD. 
THE UMKI...NOGAPS...ECMWF...AND GFDL FIELDS SHOW LANDFALL IN
EASTERN MEXICO OR GUATEMALA IN 36 TO 48 HOURS.  THIS REQUIRES
ANOTHER EASTWARD ADJUSTMENT TO THE TRACK FORECAST...ESPECIALLY
BEYOND 48 HOURS. THE FORECAST TRACK IS CLOSE TO THE UKMET AND
NOGAPS SOLUTIONS...BUT IS SLOWER THAN THE GFDL. THE NEW OFFICIAL
FORECAST SHOWS LANDFALL OVER EASTERN MEXICO OR GUATEMALA IN ABOUT
36 HOURS.  THIS HAS PROMPTED THE ISSUANCE OF A TROPICAL STORM WATCH
FROM SIPACATE GUATEMALA TO BARRA DE TONALA MEXICO.
 
BARBARA IS LOCATED OVER WARM WATER AND IN A LOW SHEER ENVIRONMENT.
ADDITIONAL STRENGTHENING IS FORECAST...BUT HOW MUCH INTENSIFICATION
IS THE QUESTION.  BOTH THE SHIPS AND GFDL MODELS SHOW GRADUAL
INTENSIFICATION DURING THE NEXT DAY OR SO AS DOES THE NHC INTENSITY
FORECAST.  THEREAFTER....INTERACTION WITH LAND COULD HALT ANY
ADDITIONAL STRENGTHENING. 

FORECAST POSITIONS AND MAX WINDS
 
INITIAL      01/1500Z 13.0N  94.5W    40 KT
 12HR VT     02/0000Z 13.3N  93.9W    45 KT
 24HR VT     02/1200Z 13.9N  93.5W    50 KT
 36HR VT     03/0000Z 14.6N  93.3W    50 KT
 48HR VT     03/1200Z 15.4N  93.2W    50 KT
 72HR VT     04/1200Z 16.6N  93.3W    25 KT...INLAND
 96HR VT     05/1200Z...DISSIPATED
 
$$
FORECASTER BROWN/AVILA