ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM NARDA DISCUSSION NUMBER   5
NATIONAL WEATHER SERVICE MIAMI FL
8 AM PDT SUN OCT 21 2001
 
SATELLITE IMAGERY INDICATES THAT THE STORM IS INTENSIFYING.  DVORAK
T-NUMBERS ARE NOW 3.5...WHICH CORRESPONDS TO 55 KNOTS.  THERE IS
DECENT UPPER-LEVEL OUTFLOW OVER THE SYSTEM...AND FURTHER
STRENGTHENING IS EXPECTED IN THE SHORT TERM.  HOWEVER...NARDA SHOULD
BEGIN TO FEEL THE EFFECTS OF INCREASING WESTERLY SHEAR IN A DAY OR
SO...AND COMMENCE WEAKENING.  THIS IS REFLECTED IN THE OFFICIAL WIND
SPEED FORECAST...WHICH IS SIMILAR TO THE SHIPS GUIDANCE.  THE LATEST
GFDL MODEL RUN CALLS FOR MORE STRENGTHENING THAN SHOWN HERE...BUT
THAT MODEL HAS BEEN KNOWN TO HAVE A HIGH BIAS FOR INTENSITY
PREDICTION...PARTICULARLY IN CASES OF STRONG SHEAR.

THE INITIAL MOTION ESTIMATE...295/12...IS ONLY SLIGHTLY TO THE RIGHT
OF THAT FROM THE PREVIOUS ADVISORY.  THE TRACK FORECAST REASONING IS
BASICALLY UNCHANGED.  A MID-LEVEL RIDGE IS EXPECTED TO MAINTAIN THE
WEST-NORTHWESTWARD STEERING FOR THE NEXT SEVERAL DAYS.  THE OFFICIAL
TRACK FORECAST IS ALONG THE SAME GENERAL TRAJECTORY AS THE GFDL/
U.K. MET/NOGAPS/AVN MODEL CONSENSUS...GUNA...ALBEIT A LITTLE
SLOWER.  THE GFDL TRACK IS SLOWER THAN...AND TO THE RIGHT OF...THE
OFFICIAL FORECAST.

FORECASTER PASCH
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     21/1500Z 13.7N 130.1W    55 KTS
12HR VT     22/0000Z 14.5N 131.8W    65 KTS
24HR VT     22/1200Z 15.5N 134.2W    65 KTS
36HR VT     23/0000Z 16.2N 136.6W    60 KTS
48HR VT     23/1200Z 17.0N 139.0W    50 KTS
72HR VT     24/1200Z 18.5N 143.5W    40 KTS
 
 
NNNN