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TROPICAL DEPRESSION EIGHTEEN-E DISCUSSION NUMBER   1
NATIONAL WEATHER SERVICE MIAMI FL
2 PM PDT WED OCT 25 2000
 
IN HINDSIGHT...IT APPEARS THAT THE DISTURBANCE SOUTHWEST OF
MANZANILLO WAS PROBABLY A TROPICAL STORM OVERNIGHT.  THIS MORNING A
TIGHT LOW-LEVEL CLOUD SWIRL EMERGED AND HAS BEEN GRADUALLY
SEPARATING FROM THE DEEP CONVECTION EVER SINCE.  THE CIRCULATION
DOES HAVE AMPLE BANDS OF SHALLOW CONVECTION...ENOUGH TO QUALIFY AS A
TROPICAL CYCLONE.  A QUIKSCAT PASS AROUND 13Z THIS MORNING SUGGESTED
THAT WINDS THEN WERE IN THE 35-40 KT RANGE.  NOW...WITH THE EXPOSED
CENTER...THE WINDS HAVE PRESUMABLY COME DOWN A BIT.   SHEAR IS
EXPECTED TO REMAIN HIGH FOR THE NEXT DAY OR SO BUT WILL CHANGE
ORIENTATION FROM WESTERLY TO NORTHERLY.  AFTER THAT...THERE MAY BE
AN OPPORTUNITY FOR SOME STRENGTHENING. 

THE INITIAL MOTION IS 275/14.  THE DEPRESSION IS LOCATED SOUTH OF A
LOW- TO MID-LEVEL RIDGE THAT IS PROVIDING A BASIC WESTWARD STEERING
FLOW.  UPSTREAM OF THIS RIDGE IS A LARGE CUTOFF LOW NEAR 40N127W. 
GLOBAL MODELS ARE FORECASTING AMPLIFICATION OF A TROUGH OUT OF THIS
CUTOFF THAT WEAKENS THE RIDGE AND COULD RESULT IN A SLOWING OF THE
FORWARD MOTION OVER THE NEXT DAY OR TWO.  A COMPLICATING FACTOR WILL
BE HOW LONG THE CYCLONE REMAINS IN A SHEARED STATE AND FOLLOWS A
SHALLOWER LAYER FLOW.  THE OFFICIAL FORECAST FAVORS THE NOGAPS
SOLUTION...WHICH KEEPS A MUCH WEAKER SYSTEM THAN THE AVN...AND
CONSEQUENTLY TAKES THE DEPRESSION FARTHER TO THE WEST.
 
FORECASTER FRANKLIN
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     25/2100Z 10.4N 112.1W    30 KTS
12HR VT     26/0600Z 10.6N 114.0W    30 KTS
24HR VT     26/1800Z 10.8N 115.9W    30 KTS
36HR VT     27/0600Z 11.0N 117.5W    35 KTS
48HR VT     27/1800Z 11.5N 119.0W    40 KTS
72HR VT     28/1800Z 13.0N 122.0W    45 KTS
 
 
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