Tropical Depression FIFTEEN-E Discussion 2

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PACIFIC BASIN (EPAC)

 

Tropical Depression FIFTEEN-E

 

 

000

WTPZ45 KNHC 120212

TCDEP5

TROPICAL DEPRESSION FIFTEEN-E DISCUSSION NUMBER 2

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

8 PM PDT MON OCT 11 2004

 

A 11/2345Z TRMM OVERPASS CLEARLY SHOWED THAT TD-15E HAS MOVED

NORTHWESTWARD FROM ITS PREVIOUS LOCATION. IT ALSO INDICATED A SMALL

BUT TIGHTLY CURVED CONVECTIVE BAND THAT WRAPPED ABOUT HALF WAY

AROUND THE LOW-LEVEL CENTER. THIS WOULD SUPPORT THE T2.5...OR 35

KT...INTENSITY ESTIMATE FROM THE TAFB. HOWEVER...I AM HOLDING THE

INTENSITY AT DEPRESSION STRENGTH GIVEN THAT THE CONVECTION ...

ALBEIT QUITE COLD AT -80C AND COLDER...HAS ONLY PERSISTED FOR

FOR THE PAST 4 HOURS OR SO.

 

THE INITIAL MOTION ESTIMATE IS 295/04. A GRADUAL TURN TOWARD THE

WEST IS EXPECTED AFTER 12 HOURS AS A MID-LEVEL RIDGE IS FORECAST TO

BUILD SLOWLY WESTWARD TO THE NORTH OF THE CYCLONE. THE SPECIFIC

GLOBAL MODEL GUIDANCE IS OF LITTLE HELP SINCE THE MODELS AT 12Z AND

18Z EITHER INITIALIZED THE CENTER TO FAR EAST LIKE NOGAPS...OR

BARELY INITIALIZED IT AT ALL LIKE THE UKMET AND CANDIAN MODELS. THE

GFS DID INITIALIZE THE VORTEX PROPERLY...BUT IT QUICKLY WEAKENS IT

AND ALLOWS IT TO GET ABSORBED INTO THE THERMAL TROUGH THAT

TYPICALLY LIES ALONG THE MEXICAN COAST. THE TRACK FORECAST LEANS

HEAVILY TOWARD THE MEDIUM BAM AND THE GFS 10-MEMBER ENSEMBLE MEAN

MODELS...AND THE DEVELOPING MID-LEVEL SYNOPTIC PATTERN.

 

THE DEPRESSION HAS A VERY SMALL BUT TIGHT LOW-LEVEL WIND FIELD AS

NOTED IN EARLIER VISIBLE IMAGERY AND THE RECENT TRMM MICROWAVE

OVERPASS. AS SUCH...IT IS SUSC

EPTIBLE TO RAPID FLUCTUATIONS IN

STRENGTH. THE CURRENT BURST OF DEEP CONVECTION MAY HAVE VERTICALLY

STRETCHED THE VORTEX ENOUGH TO PRODUCE TROPICAL STORM WINDS NEAR

AND TO THE SOUTH OF THE CENTER. HOWEVER...THE LACK OF PERSISTENT

CONVECTION PRECLUDES NAMING THE SYSTEM AT THIS TIME. THE SHIPS

MODEL KEEPS THE CYCLONE OVER 29C-30C SSTS AND UNDER LESS THAN 10 KT

OF SHEAR FOR THE NEXT 72 HOURS...SO STEADY STRENGTHENING SEEMS IN

ORDER. IF DRY MID-LEVEL AIR EAST OF THE CYCLONE DOES NOT GET DRAWN

INTO THE SYSTEM...THEN MORE INTENSIFICATION COULD OCCUR AFTER 36HR.

 

FORECASTER STEWART

 

FORECAST POSITIONS AND MAX WINDS

 

INITIAL 12/0300Z 14.9N 97.2W 30 KT

12HR VT 12/1200Z 15.0N 98.0W 35 KT

24HR VT 13/0000Z 15.1N 99.2W 45 KT

36HR VT 13/1200Z 15.2N 100.7W 55 KT

48HR VT 14/0000Z 15.1N 102.4W 65 KT

72HR VT 15/0000Z 15.0N 105.0W 70 KT

96HR VT 16/0000Z 15.5N 107.5W 75 KT

120HR VT 17/0000Z 16.5N 110.0W 70 KT

 

 

$$