990 
 WTPZ42 KNHC 290235
 TCDEP2
  
 TROPICAL STORM BARBARA DISCUSSION NUMBER   2
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP022013
 800 PM PDT TUE MAY 28 2013
  
 THE STRUCTURE OF BARBARA HAS IMPROVED DRAMATICALLY SINCE THE LAST
 ADVISORY...AND INFRARED SATELLITE IMAGES HAVE EVEN SHOWN AN
 EYE-LIKE FEATURE DURING THE PAST COUPLE OF HOURS.  DVORAK ESTIMATES
 FROM TAFB AND SAB WERE 35 KT AT 0000 UTC...BUT THE SATELLITE
 PRESENTATION HAS IMPROVED SUFFICIENTLY SINCE THAT TIME TO START
 WITH AN ADVISORY INTENSITY OF 40 KT.
  
 A LITTLE BIT OF RELOCATION OF THE CENTER WAS REQUIRED BASED ON
 RECENT SATELLITE DATA...BUT IT APPEARS THAT BARBARA NOW HAS A
 MOTION OF 030/3 KT.  THE CYCLONE IS MOVING NORTH-NORTHEASTWARD INTO
 A BREAK IN THE SUBTROPICAL RIDGE...AND IT SHOULD BEGIN TO
 ACCELERATE OVER THE NEXT DAY OR SO AS A MID-LATITUDE TROUGH DEEPENS
 OVER THE SOUTHERN UNITED STATES.  THE NHC FORECAST TRACK BRINGS THE
 CENTER OF BARBARA INLAND ALONG THE SHORE OF THE GULF OF TEHUANTEPEC
 IN 12 TO 24 HOURS.
  
 ANALYSES FROM UW-CIMSS INDICATE THAT BARBARA IS EMBEDDED IN A NARROW
 ZONE OF NEGLIGIBLE SHEAR...AND THE CYCLONE IS OVER EXTREMELY WARM
 WATER ON THE ORDER OF 30 DEGREES CELSIUS.  GIVEN THE CURRENT
 STRUCTURE OF BARBARA...ITS RELATIVELY SMALL INNER CORE...AND THE
 FAVORABLE ENVIRONMENTAL CONDITIONS...A FAIRLY STEEP INCREASE IN
 INTENSITY IS POSSIBLE BEFORE THE CENTER OF THE STORM REACHES THE
 COAST.  THE UPDATED NHC INTENSITY FORECAST IS HIGHER THAN THE
 STATISTICAL GUIDANCE...FOLLOWING A TREND OF RAPID INTENSIFICATION IN
 THE VERY SHORT-TERM...AND BRINGS BARBARA TO 55 KT IN 12 HOURS. 
 BARBARA COULD GAIN A LITTLE MORE STRENGTH JUST BEFORE REACHING THE
 COAST...BUT TIME WILL BE THE LIMITING FACTOR.  QUICK WEAKENING IS
 EXPECTED AFTER LANDFALL...AND THE LOW-LEVEL CIRCULATION SHOULD
 DISSIPATE OVER THE ISTHMUS OF TEHUANTEPEC BY 48 HOURS...IF NOT
 SOONER.
  
 DUE TO THE EXPECTED SLOW MOTION OF BARBARA AND ITS REMNANTS...AS
 WELL AS THE MOUNTAINOUS TERRAIN IN AND NEAR THE LANDFALL AREA...THE
 BIGGEST HAZARD WILL LIKELY BE HEAVY RAINFALL AND THE POTENTIAL FOR
 FLASH FLOODING AND MUD SLIDES.
 
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  29/0300Z 14.5N  95.7W   40 KT  45 MPH
  12H  29/1200Z 15.3N  95.1W   55 KT  65 MPH
  24H  30/0000Z 16.7N  94.7W   45 KT  50 MPH...INLAND
  36H  30/1200Z 17.9N  94.5W   30 KT  35 MPH...INLAND
  48H  31/0000Z...DISSIPATED
  
 $$
 FORECASTER BERG/BEVEN