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Tropical Depression IRWIN (Text)

ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM
 
TROPICAL DEPRESSION IRWIN DISCUSSION NUMBER  42
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP112011
800 AM PDT SUN OCT 16 2011

DEEP CONVECTION RE-DEVELOPED...AGAIN...NEAR THE CENTER OF THE
TROPICAL CYCLONE AROUND 0600 UTC...AND IT HAS EXPANDED SINCE THAT
TIME. HOWEVER...CLOUD TOPS HAVE WARMED A LITTLE DURING THE PAST FEW
HOURS. SATELLITE CLASSIFICATIONS WERE 2.0/30 KT FROM BOTH TAFB AND
SAB...SO THE INITIAL WIND SPEED IS SET AT THAT VALUE. IRWIN COULD
BE NEARING TROPICAL STORM STRENGTH AGAIN...AS INDICATED BY THE
LATEST ADT ESTIMATES FROM UW-CIMSS. HOWEVER...THE LONG-TERM TREND
SHOULD BE FOR IRWIN TO WEAKEN DUE TO INCREASING EASTERLY SHEAR AND
DRY AIR.  THE OFFICIAL INTENSITY FORECAST IS BASICALLY UNCHANGED
FROM EARLIER...SHOWING IRWIN DEGENERATING INTO A REMNANT LOW IN 36
TO 48 HOURS.

SATELLITE FIXES INDICATE THAT IRWIN IS NOW MOVING SOUTHWESTWARD...
AND THE LATEST INITIAL MOTION ESTIMATE IS 230/4. THE STEERING
CURRENTS FOR THE CYCLONE ARE EXPECTED TO REMAIN WEAK FOR THE NEXT
SEVERAL DAYS. THIS WILL ALLOW IRWIN...OR ITS REMNANTS...TO MEANDER
IN THE LOW- TO MID-LEVEL FLOW...WHICH SHOULD TAKE IT FIRST WESTWARD
AND THEN BACK SOUTHEASTWARD. THE OFFICIAL FORECAST HAS BEEN
ADJUSTED NORTHWARD TO COME INTO BETTER AGREEMENT WITH THE LATEST
GUIDANCE.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  16/1500Z 14.1N 107.8W   30 KT  35 MPH
 12H  17/0000Z 14.1N 108.3W   30 KT  35 MPH
 24H  17/1200Z 14.2N 109.0W   25 KT  30 MPH
 36H  18/0000Z 14.2N 109.3W   25 KT  30 MPH
 48H  18/1200Z 14.1N 109.4W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  19/1200Z 13.7N 108.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  20/1200Z 13.5N 108.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  21/1200Z...DISSIPATED
 
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FORECASTER CANGIALOSI
 
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