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Hurricane DARBY (Text)

ZCZC MIATCDEP5 ALL
TTAA00 KNHC DDHHMM
HURRICANE DARBY DISCUSSION NUMBER  15
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2 AM PDT FRI JUL 30 2004
 
DARBY CONTINUES TO WEAKEN AS ITS DEEP CONVECTION IS DECREASING IN
SIZE AND ORGANIZATION.  THE INITIAL WIND SPEED ESTIMATE IS DECREASED
TO 65 KNOTS.  THE SHIPS AND GFS MODELS DISSIPATE DARBY IN 36 HOURS
UNDER INCREASING VERTICAL SHEAR AND COOLER SSTS.  HOWEVER THE
NOGAPS AND UKMET HOLD ON TO A STRONG TROPICAL CYCLONE FOR 120 HOURS
AND THE GFDL DISSPATES THE SYSTEM AT 120 HOURS.  AS A COURSE OF
LEAST REGRET...THE OFFICIAL FORECAST GOES OUT TO 120 HOURS WITH A
30 KNOT DEPRESSION.  IT IS OF COURSE MORE LIKELY THAT DARBY WILL
NOT LAST THAT LONG.
 
THE INITIAL MOTION ESTIMATE IS 285/11.  THE MODELS ARE IN GOOD
AGREEMENT ABOUT A MOTION JUST NORTH OF DUE WESTWARD FOR AT LEAST 72
HOURS.  ONLY THE NOGAPS SHOWS A TURN TOWARD THE NORTH AFTER 72
HOURS AS THE CYCLONE ENCOUNTERS A WEAKNESS IN THE RIDGE TO THE
NORTH...THIS IS LIKELY DUE TO THE NOGAPS KEEPING A STRONGER SYSTEM.
THE GFDL AND UKMET ARE MOSTLY WESTWARD FOR 120 HOURS.  THE OFFICIAL
FORECAST FOLLOWS A CONCENSUS OF THE TRACK GUIDANCE AND IS SLIGHTLY
NORTH OF THE PREVIOUS OFFICIAL FORECAST AFTER 72 HOURS.
 
FORECASTER LAWRENCE
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      30/0900Z 18.6N 130.8W    65 KT
 12HR VT     30/1800Z 19.0N 132.6W    50 KT
 24HR VT     31/0600Z 19.3N 135.0W    40 KT
 36HR VT     31/1800Z 19.5N 138.1W    30 KT
 48HR VT     01/0600Z 19.7N 140.9W    30 KT
 72HR VT     02/0600Z 19.8N 146.0W    30 KT
 96HR VT     03/0600Z 20.5N 151.0W    30 KT
120HR VT     04/0600Z 22.0N 154.0W    30 KT
 
 
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