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Tropical Storm LORENZO (Text)

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TROPICAL STORM LORENZO DISCUSSION NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132013
500 AM AST TUE OCT 22 2013

ALTHOUGH DEEP CONVECTION HAS BEEN INCREASING DURING THE PAST SEVERAL
HOURS...MICROWAVE IMAGES INDICATE THAT THE LOW-LEVEL CENTER IS
LOCATED NEAR THE SOUTHWESTERN EDGE OF THIS DEEP CLOUDINESS.  THE
LATEST DVORAK CLASSIFICATIONS FROM TAFB...SAB...AND UW-CIMSS ADT
SUPPORT MAINTAINING THE INITIAL WIND SPEED AT 35 KT.  LORENZO COULD
STRENGTHEN A LITTLE TODAY BEFORE NORTHWESTERLY WIND SHEAR INCREASES
SUBSTANTIALLY.  THE GFS AND ECMWF MODELS SHOW THE VERTICAL
CIRCULATION BECOMING HIGHLY TILTED IN ABOUT 24 HOURS DUE TO THE
STRONG SHEAR.  IN ADDITION...DRIER AIR AND DECREASING SEA SURFACE
TEMPERATURES ALONG THE EXPECTED TRACK OF LORENZO SHOULD AID IN THE
WEAKENING PROCESS.  THE CYCLONE IS EXPECTED TO DISSIPATE IN 3 TO 4
DAYS...BUT THERE IS SOME GUIDANCE THAT SHOWS THIS OCCURRING SOONER.

LORENZO IS GRADUALLY TURNING TO THE RIGHT...AND THE LATEST INITIAL
MOTION ESTIMATE IS 070/7.  AN EAST-NORTHEASTWARD TO EASTWARD MOTION
IS EXPECTED DURING THE NEXT DAY OR SO WHILE THE STORM MOVES IN THE
WESTERLY FLOW ON THE NORTH SIDE OF A SUBTROPICAL RIDGE.  THE
WEAKENING CYCLONE IS FORECAST TO TURN NORTHEASTWARD BY LATE
WEDNESDAY OR THURSDAY AHEAD OF AN APPROACHING COLD FRONT.  THE
MODELS ARE IN GOOD AGREEMENT...AND ONLY SMALL CHANGES WERE MADE TO
THE PREVIOUS TRACK FORECAST.

FORECAST POSITIONS AND MAX WINDS
 
INIT  22/0900Z 29.5N  53.0W   35 KT  40 MPH
 12H  22/1800Z 29.7N  51.7W   40 KT  45 MPH
 24H  23/0600Z 29.9N  50.3W   35 KT  40 MPH
 36H  23/1800Z 30.2N  49.3W   35 KT  40 MPH
 48H  24/0600Z 30.8N  48.3W   30 KT  35 MPH
 72H  25/0600Z 32.8N  45.2W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  26/0600Z...DISSIPATED
 
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FORECASTER CANGIALOSI
 
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