000
WTPZ44 KNHC 010831
TCDEP4
TROPICAL STORM JULIETTE DISCUSSION NUMBER   9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP142007
200 AM PDT MON OCT 01 2007
 
A SEQUENCE OF MICROWAVE PASSES BETWEEN 00Z AND 04Z SUGGEST THAT THE
CENTER OF JULIETTE IS A LITTLE EAST OF THE PREVIOUS TRACK...AND
LAGGING BEHIND THE DEEP CONVECTION. A QUIKSCAT PASS AT 02Z ALSO
PLACED THE CENTER ON THE SOUTHEAST EDGE OF THE CONVECTION. THE
QUIKSCAT DATA INCLUDED A 50 KT VECTOR THAT MIGHT HAVE BEEN
VALID...BUT GIVEN THAT THE CENTER AND THE CONVECTION SEEM TO BE
SEPARATING...I'D PREFER TO KEEP THE ADVISORY INTENSITY AT 45 KT.
ALONG THE FORECAST TRACK...SOUTHERLY WIND SHEAR WILL CONTINUE AS
THE CYCLONE PASSES OVER PROGRESSIVELY COOLER WATERS...SO A
WEAKENING TREND APPEARS IMMINENT.  THE OFFICIAL FORECAST FOLLOWS
THE PREVIOUS ADVISORY AND THE LGEM STATISTICAL MODEL. 
 
WITH THE EASTWARD ADJUSTMENT OF THE TRACK...THE INITIAL MOTION
ESTIMATE IS 330/9. THE TRACK FORECAST PHILOSOPHY IS UNCHANGED FROM
THE PREVIOUS ADVISORY. JULIETTE HAS RECENTLY BEEN MOVING IN BETWEEN
A LOW- TO MID-LEVEL RIDGE OVER MEXICO AND A MID-LEVEL TROUGH TO ITS
WEST. AS THE CYCLONE SPINS DOWN IT SHOULD DECELERATE IN THE WEAK
LOWER-LEVEL FLOW WEST OF THE BAJA CALIFORNIA PENINSULA. THE
OFFICIAL FORECAST REMAINS ALONG THE LEFT SIDE OF THE TRACK GUIDANCE
ENVELOPE...AND COMES ESSENTIALLY TO A HALT AFTER 36 HOURS AROUND
THE TIME OF DISSIPATION.  IF THE CYCLONE SUCCUMBS TO THE SHEAR
EARLIER THAN EXPECTED...AND THIS PROCESS MAY ALREADY BE
BEGINNING...THEN THE STALL WOULD OCCUR EARLIER. 
 

FORECAST POSITIONS AND MAX WINDS
 
INITIAL      01/0900Z 21.0N 114.8W    45 KT
 12HR VT     01/1800Z 22.1N 115.3W    40 KT
 24HR VT     02/0600Z 23.2N 115.7W    35 KT
 36HR VT     02/1800Z 24.0N 116.0W    30 KT
 48HR VT     03/0600Z 24.3N 116.0W    25 KT...REMNANT LOW
 72HR VT     04/0600Z 24.5N 116.0W    20 KT...REMNANT LOW
 96HR VT     05/0600Z...DISSIPATED
 
$$
FORECASTER FRANKLIN