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...FOR INTERGOVERNMENTAL USE ONLY...
TROPICAL STORM ANDREW DISCUSSION NUMBER   4
NATIONAL WEATHER SERVICE MIAMI FL
5 PM EDT MON AUG 17 1992
 
ALL FIXES FROM VISIBLE SATELLITE PICTURES INDICATE T3.0/3.0... OR 45
KNOTS.  HOWEVER... WE WILL ONLY INCREASE THE WINDS TO 40 KNOTS AT
THIS TIME SINCE THE SYSTEM SEEMS TO BE PULSATING WITH PERIODS OF
DEEP CONVECTION.

INITIAL MOTION OF 285/20 KNOTS STILL LOOKS GOOD.  HOWEVER... THERE
IS A MARKED DIFFERENCE IN THE MODEL TRACKS COMPARED WITH THE
PREVIOUS PACKAGE.  IN THE PREVIOUS PACKAGE... THE DYNAMIC MODELS ALL
HAD THE FORECAST TRACKS SOUTH OF CLIMATOLOGY... WHEREAS THE 1800 UTC
RUNS ALL HAD THE TRACKS NORTH OF CLIMATOLOGY.  AVN GUIDANCE SHOWS
THE UPPER LOW NORTHWEST OF THE SYSTEM MOVING WEST SOUTHWESTWARD...
AS TYPICAL... BUT OPENS IT TO A TROUGH DURING THE PERIOD.  THAT
CREATES A POSSIBLE SPLIT IN THE STEERING CURRENTS WITH THE NORTHERN
STREAM CURVING ANDREW AWAY FROM THE ANTILLES.  THE SOUTHERN STREAM
WOULD BE MORE WESTERLY WHICH WOULD IMPACT THE LEEWARDS.  WE WILL GO
WITH THE LATTER SCENARIO AND STILL SHOW A POSSIBLE THREAT TO THE
LEEWARDS UNTIL THE SITUATION BECOMES CLEARER.

THE INTENSITY SCENARIO FOLLOWS CLIMATOLOGY AND THE HRD EXPERIMENTAL
INTENSITY FORECAST SCHEME....SHIPS92. 

GERRISH
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     17/2100Z 13.4N  45.3W    40 KTS
12HR VT     18/0600Z 14.1N  48.3W    45 KTS
24HR VT     18/1800Z 15.1N  51.9W    50 KTS
36HR VT     19/0600Z 16.0N  55.5W    50 KTS
48HR VT     19/1800Z 17.0N  58.5W    55 KTS
72HR VT     20/1800Z 19.0N  63.5W    55 KTS