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TROPICAL DEPRESSION FOUR-E DISCUSSION NUMBER   1
NATIONAL WEATHER SERVICE MIAMI FL
2 PM PDT FRI JUL 20 2001

AN AREA OF DISTURBED WEATHER HAS GRADUALLY BECOME BETTER ORGANIZED 
OVER THE PAST 24 HOURS.  A QUIKSCAT PASS THIS MORNING SHOWED A 
CLOSED CIRCULATION COINCIDENT WITH A LOW-LEVEL CLOUD CIRCULATION
AND ALTHOUGH THE DEEP CONVECTION IS DISORGANIZED...THERE IS PLENTY 
OF IT.  THEREFORE THE SYSTEM IS UPGRADED TO TROPICAL DEPRESSION 
NUMBER FOUR.

THERE IS NOT MUCH OF A PAST TRACK TO HELP DETERMINE THE INITIAL 
MOTION.  THE ESTIMATE IS 300/03 BASED ON LOOKING AT A 24 HOUR 
INFRARED LOOP.  MODEL GUIDANCE SUGGESTS A CONTINUED WEST-NORTHWEST 
MOTION THROUGH 72 HOURS WITH A VERY WEAK SUBTROPICAL RIDGE TO THE 
NORTH.

THE FORECAST TRACK MOVES OVER SLIGHTLY COOLER WATER DURING THE NEXT 
72 HOURS WHICH LIMITS THE INTENSIFICATION TO ONLY 45 KNOTS...IN 
AGREEMENT WITH THE SHIPS MODEL.
 
FORECASTER LAWRENCE
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     20/2100Z 13.7N 117.2W    30 KTS
12HR VT     21/0600Z 14.0N 117.9W    35 KTS
24HR VT     21/1800Z 14.5N 118.8W    40 KTS
36HR VT     22/0600Z 15.0N 119.9W    45 KTS
48HR VT     22/1800Z 15.8N 121.0W    45 KTS
72HR VT     23/1800Z 17.5N 123.5W    35 KTS
 
 
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