000
WTPZ42 KNHC 020831
TCDEP2
TROPICAL STORM BARBARA DISCUSSION NUMBER  15
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP022007
200 AM PDT SAT JUN 02 2007
 
AN 0612Z TRMM PASS JUST IN CONFIRMS THAT BARBARA REMAINS BASICALLY
ON TRACK...WITH AN INITIAL MOTION OF 040/7. MODEL GUIDANCE IS SPLIT
ON WHETHER BARBARA WILL CONTINUE ON THIS GENERAL TRACK INLAND...OR
MAKE A SHARP LEFT TURN AND PERHAPS PARALLEL THE COAST OFFSHORE. IN
SOME CASES EVEN INDIVIDUAL MODELS ARE SPLIT. THE ECMWF...FOR
EXAMPLE...TAKES THE 850 MB CENTER INLAND BUT THE 500 MB CENTER
WESTWARD. THERE ALSO APPEAR TO BE SOME TRACKER ISSUES IN THE GFDL
MODEL WITH THE TERRAIN OF SOUTHEASTERN MEXICO AND GUATEMALA. WATER
VAPOR IMAGERY DOES INDICATE SOME EASTERLY SHEAR THAT WOULD BE
CONSISTENT WITH THIS PATTERN...BUT I PREFER TO FOLLOW THE LOW-LEVEL
VORTICITY MAXIMA IN THE GFDL...NOGAPS...AND ECMWF...WHICH ALL
INDICATE A BASIC CONTINUATION OF THE TRACK INLAND. THE TRMM PASS
DID SHOW THAT THE MID-LEVEL CENTER WAS DISPLACED A LITTLE TO THE
NORTHWEST OF THE LOW-LEVEL CENTER...SO PERHAPS THE SEPARATION
FORECAST BY THE ECMWF IS BEGINNING TO OCCUR.
 
THE STRUCTURE OF BARBARA DOES NOT APPEAR TO HAVE CHANGED MUCH...
ALTHOUGH I HAVE REDUCED THE WIND RADII BASED ON THE LAST QUIKSCAT
PASS. A WINDSAT PASS BACK AT 2339Z SHOWED GOOD BANDING AND A
LOW-LEVEL EYE-LIKE FEATURE...BUT THE LATEST TRMM IMAGE SUGGESTS THAT
BARBARA HAS NOT STRENGTHENED. THE INITIAL INTENSITY IS HELD AT 45
KT AND LITTLE CHANGE IN STRENGTH IS EXPECTED PRIOR TO LANDFALL.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      02/0900Z 14.4N  92.7W    45 KT
 12HR VT     02/1800Z 15.0N  92.5W    40 KT...INLAND
 24HR VT     03/0600Z 15.6N  92.5W    25 KT...DISSIPATING
 36HR VT     03/1800Z...DISSIPATED
 
$$
FORECASTER FRANKLIN