000
WTNT42 KNHC 181447
TCDAT2
TROPICAL STORM JULIA DISCUSSION NUMBER  26
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL122010
1100 AM AST SAT SEP 18 2010
 
VISIBLE SATELLITE IMAGES INDICATE THAT STRONG NORTHERLY SHEAR HAS
DISPLACED DEEP CONVECTION ASSOCIATED WITH JULIA TO THE SOUTHEAST OF
THE NOW EXPOSED LOW-LEVEL CENTER.  AS A RESULT...DVORAK T-NUMBERS
ARE DECREASING AS QUICKLY AS CONSTRAINTS WILL ALLOW.  A BLEND OF
T/CI NUMBERS FROM TAFB/SAB REPRESENT THE BASIS FOR AN INITIAL
INTENSITY OF 45 KT FOR THIS ADVISORY.  THE PERSISTENCE OF STRONG
SHEAR ASSOCIATED WITH THE OUTFLOW OF IGOR AND PROGRESSIVELY COOLER
WATERS ALONG THE FORECAST TRACK SHOULD LEAD TO A CONTINUED
WEAKENING.  THE NHC OFFICIAL FORECAST IS NEAR THE STATISTICAL-
DYNAMICAL GUIDANCE...AND INDICATES JULIA BECOMING A REMNANT LOW IN
48 HOURS.  HOWEVER...JULIA COULD DEGENERATE INTO A REMNANT LOW
SOONER THAN CURRENTLY FORECAST.  ULTIMATELY...THE REMNANT
CIRCULATION OF JULIA COULD BE ABSORBED BY LARGE HURRICANE IGOR AS
IGOR UNDERGOES EXTRATROPICAL TRANSITION BEYOND 72 HOURS.

THE INITIAL MOTION ESTIMATE HAS SHIFTED A LITTLE MORE TO THE RIGHT
COMPARED TO BEFORE AND IS NOW 320/16.  THE MODEL GUIDANCE IS IN
GOOD AGREEMENT...SHOWING A TRACK BENDING TOWARD THE NORTH-NORTHWEST
LATER TODAY AND TURNING NORTHWARD TOMORROW AS JULIA MOVES AROUND A
SUBTROPICAL RIDGE TO THE EAST.  THE OFFICIAL NHC FORECAST IS NEAR
THE THE PREVIOUS ONE...CLOSE TO THE MIDDLE OF THE GUIDANCE ENVELOPE
BUT SLIGHTLY RIGHT OF THE MULTI-MODEL CONSENSUS.
  
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      18/1500Z 28.9N  51.0W    45 KT
 12HR VT     19/0000Z 31.1N  51.9W    40 KT
 24HR VT     19/1200Z 33.5N  51.8W    35 KT
 36HR VT     20/0000Z 35.5N  50.3W    30 KT
 48HR VT     20/1200Z 37.0N  48.0W    25 KT...POST-TROP/REMNT LOW
 72HR VT     21/1200Z 40.5N  43.0W    20 KT...POST-TROP/REMNT LOW
 96HR VT     22/1200Z...DISSIPATED
 
$$
FORECASTER KIMBERLAIN