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...FOR INTERGOVERNMENTAL USE ONLY...
TROPICAL STORM NORA DISCUSSION NUMBER   8
NATIONAL WEATHER SERVICE MIAMI FL
630 PM PST FRI NOV 08 1991
 
ATTN WSFOS NMC F/D
 
A RAGGED EYE HAS APPEARED OCCASIONALLY OVER THE PAST FEW HOURS
AND...WITH TSAF AND SAB DVORAK ESTIMATES NOW BOTH AT LEAST 4.0...
NORA IS UPGRADED TO A 70 KT HURRICANE.  THE CENTER SEEMS TO BE
MOVING NORTH OF DUE WEST NOW...BUT THE INITIAL MOTION OF          IS
SOMEWHAT UNCERTAIN DUE TO LOWER CONFIDENCE IN FIXES MADE BEFORE THE
EYE FORMED NORTH OF PREVIOUS TRACK.

AVN MODEL CONTINUES TO SHOW TROUGH APPROACHING NORA FROM THE WEST. 
PRIMARY QUESTION IS WHETHER THE HURRICANE WILL BECOME SHEARED OR
RECURVE?  RECURAVATURE IS POSSIBLE BUT FOR NOW THE SHEARING OPTION
IS PREFERRED BECAUSE THE MODEL SHOWS LOW-LEVEL ENE FLOW TO PERSIST
NEAR HURRICANE...WHILE FLOW FROM 700 MB UPWARDS BECOMES SW AFTER 36
HOURS.  BY 72 HOURS AVN SHOWS 45 KT SW WINDS OVER NORA AT 200 MB. 
MID- AND UPPER-LEVEL MOISTURE MAY BEGIN STREAMING NE FROM NORA BY 36
HOURS.  OFFICIAL TRACK FOLLOWS GUIDANCE MODELS AND LEANS MORE TOWARD
BAMM AND BAMS BY 72 HOURS.  

SOME STRENGTHENING IS STILL POSSIBLE OVER NEXT 24 HOURS IN A
RELATIVELY FAVORABLE ENVIRONMENT.  AFTER THAT...FORECAST SHEARING
SHOULD WEAKEN NORA.

THE WIND FIELD HAS BEEN ADJUSTED A LITTLE TO BE CONSISTENT WITH THE
ASYMMETRICAL CLOUD PATTERN AND WITH RECENT INTENSIFICATION.

RAPPAPORT
 
PRELIMINARY PROG POSITIONS AND MAX WINDS
 
INITIAL     09/0300Z 12.1N 112.0W    55 KTS.
12HR VT     09/1200Z 12.0N 113.0W    55 KTS.
24HR VT     10/0000Z 12.0N 114.0W    60 KTS.
36HR VT     10/1200Z 12.0N 115.0W    60 KTS.
48HR VT     11/0000Z 12.5N 116.0W    60 KTS.
72HR VT     12/0000Z 13.0N 116.5W    55 KTS.