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TROPICAL STORM JULIETTE DISCUSSION NUMBER   7
NATIONAL WEATHER SERVICE MIAMI FL
8 PM PDT SAT SEP 22 2001
 
JULIETTE HAS BECOME MUCH BETTER ORGANIZED DURING THE PAST 6 TO 12 
HOURS AS INDICATED BY A APPEARANCE OF A DEVELOPING CDO OVER THE LAST 
FEW HOURS...ALONG WITH IMPROVED OUTER BANDING BANDING FEATURES.  IN 
FACT...AROUND 2215Z A NICE DOUGHNUT RING OF CONVECTION DEVELOPED 
AROUND THE LOW-LEVEL CIRCULATION CENTER.  THIS SUGGESTS THAT AN EYE 
MAY BE DEVELOPING OR HAS ALREADY FORMED.  THE INITIAL INTENSITY IS 
BASED ON A DVORAK SATELLITE INTENSITY ESTIMATE OF 55 KT...T3.5... 
FROM BOTH TAFB AND SAB. OUTFLOW IS GOOD IN ALL QUADRANTS AND THE 
OVERALL OUTFLOW PATTERN HAS BECOME MORE SYMMETRICAL.
 
THE INITIAL MOTION ESTIMATE IS 280/08. JULIETTE HAS MADE A SLIGHT 
JOG TO THE NORTHWEST DURING THE PAST 6 HOURS...BUT THIS IS BELIEVED 
TO BE A SHORT-TERM MOTION BASED ON RE-ORGANIZATION OF THE CENTRAL 
DEEP CONVECTION.  THE LARGE THERMAL RIDGE IN THE MID- AND 
UPPER-LEVELS ACROSS MEXICO SHOULD KEEP THE CYCLONE MOVING IN A 
GENERAL WEST OR WEST-NORTHWESTWARD DIRECTION THROUGH 36 TO 48 HOURS. 
AFTER THAT...JULIETTE IS FORECAST TO BEGIN TRACKING SLOWLY 
NORTHWESTWARD AND EVENTUALLY NORTHWARD UP THE WEST SIDE OF THE 
MID-LEVEL RIDGE. THE RIDGE IS EXPECTED TO TRANSLATE NORTHWARD AS THE 
LONGWAVE TROUGH-RIDGE PATTERN AMPLIFIES DUE TO AN APPROACHING DEEP 
PACIFIC MID-LEVEL TROUGH TO THE WEST AND A POWERFUL DIGGING TROUGH 
TO THE EAST OVER THE CENTRAL AND EASTERN U.S.  THE FORWARD SPEED WAS 
DECREASED IN THE LATTER PERIODS SINCE JULIETTE WILL BE TRYING TO 
MOVE NORTHWARD INTO THE MEAN RIDGE POSITION.  THE OFFICIAL FORECAST 
TRACK IS CLOSE TO THE PREVIOUS TRACK AFTER 24 HOURS AND IS JUST A 
LITTLE TO THE RIGHT OF THE AVN... BUT MUCH SLOWER THAN THE NOGAPS 
MODEL. IT SHOULD BE NOTED THAT THE GFDL AND GFDN MODELS TAKE THE 
CYCLONE DUE NORTH AFTER 24 HOURS AND MAKE LANDFALL NEAR ZIHUATANEJO 
MEXICO IN 60 HOURS.  GIVEN THE STRENGTH OF THE RIDGE TO THE NORTH... 
THESE TWO MODELS ARE CONSIDERED TO BE OUTLIERS AND WERE DISCOUNTED.

STEADY INTENSIFICATION IS FORECAST THROUGHOUT THE PERIOD.  
HOWEVER... I AM A LITTLE PUZZLED AT THE RATHER CONSERVATIVE SHIPS 
INTENSITY FORECAST GIVEN THAT JULIETTE IS EXPECTED TO REMAIN IN A 
LOW SHEAR...LESS THAN 8 KT...ENVIRONMENT AND TRACK OVER 29C TO 30C 
SSTS THROUGHOUT THE PERIOD.  AS A RESULT OF THE FAVORABLE SST AND 
SHEAR PATTERNS EXPECTED...I WENT A LITTLE HIGHER THAN THE SHIPS 
MODEL AT 72 HOURS.  IT IS ENTIRELY POSSIBLE THAT JULIETTE COULD 
BECOME A MAJOR HURRICANE...IF IT CAN MAINTAIN ITS IMPRESSIVE OUTFLOW 
PATTERN THROUGH 72 HOURS.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     23/0300Z 14.2N 100.7W    55 KTS
12HR VT     23/1200Z 14.6N 101.8W    65 KTS
24HR VT     24/0000Z 15.3N 103.1W    70 KTS
36HR VT     24/1200Z 15.9N 104.1W    75 KTS
48HR VT     25/0000Z 16.8N 105.3W    85 KTS
72HR VT     26/0000Z 19.0N 107.0W    95 KTS
 
 
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