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Tropical Depression TWELVE (Text)

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TROPICAL DEPRESSION TWELVE DISCUSSION NUMBER   3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT THU SEP 04 2003

THERE HAS BEEN AN INCREASE IN DEEP CONVECTION NEAR AND EAST OF THE
CENTER AND THE CLOUD PATTERN IS TAKING ON A BIT OF A COMMA SHAPE. 
BASED ON RECON FLIGHT-LEVEL DATA AND THE SATELLITE SIGNATURE THE
INTENSITY IS INCREASED TO 30 KT.  ALTHOUGH THERE IS SHEARING OVER
THE AREA DUE TO THE FLOW ON THE NORTH SIDE OF AN UPPER-LEVEL
RIDGE...THIS SHEAR IS NOT EXPECTED TO BE STRONG ENOUGH TO PREVENT
SLOW STRENGTHENING.

THE AIRCRAFT FIXES INDICATE A NORTHEASTWARD DRIFT. `THERE IS A 500
MB TROUGH TO THE NORTH OF THE DEPRESSION WHICH IS EXPECTED TO LIFT
NORTHEASTWARD...BUT SOME WEST-SOUTHWESTERLY STEERING FLOW SHOULD
REMNAIN OVER THE NORTHEAST GULF.  THEREFORE A SLOW...GENERALLY
EAST-NORTHEASTWARD...MOTION IS FORECAST.  THIS IS SOMEWHAT SLOWER
THAN IN THE PREVIOUS ADVISORY...BUT FASTER THAN MOST OF THE
GUIDANCE.  LATE IN THE PERIOD...THE CYCLONE COULD BECOME TRAPPED TO
THE SOUTH OF A SURFACE HIGH OVER THE NORTHEAST UNITED STATES.  THIS
FORECAST DOES NOT SHOW THE SYSTEM BECOMING EXTRATROPICAL BY DAY 5
SINCE THERE DOES NOT APPEAR TO BE MUCH BAROCLINICITY OFF THE
SOUTHEAST COAST...AND THE CYCLONE MAY BE IN THE VICINITY IN THE
GULF STREAM AROUND THE END OF THE PERIOD.
 
FORECASTER PASCH
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      04/0900Z 27.8N  87.4W    30 KT
 12HR VT     04/1800Z 28.2N  86.5W    30 KT
 24HR VT     05/0600Z 28.5N  85.3W    35 KT
 36HR VT     05/1800Z 28.8N  84.1W    40 KT
 48HR VT     06/0600Z 29.2N  82.5W    40 KT...INLAND
 72HR VT     07/0600Z 30.5N  79.5W    40 KT
 96HR VT     08/0600Z 32.0N  76.5W    35 KT
120HR VT     09/0600Z 34.0N  73.0W    35 KT
 
 
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