[Tropical] Tropical Cyclone Discussion

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WTNT44 KNHC 190254
TCDAT4

TROPICAL DEPRESSION HUMBERTO DISCUSSION NUMBER  35
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092013
1100 PM AST WED SEP 18 2013

HUMBERTO IS LOSING ORGANIZATION THIS EVENING.  SHORTWAVE-IR IMAGERY
INDICATES THAT THE LOW-LEVEL CIRCULATION HAS BECOME STRETCHED FROM
THE NORTHWEST TO SOUTHEAST...WITH LITTLE CONVECTION REMAINING.  THE
INITIAL INTENSITY IS LOWERED TO 30 KT IN AGREEMENT WITH THE LATEST
TAFB SATELLITE ESTIMATE.  WHILE THE CYCLONE STILL HAS SOME TIME
OVER MARGINAL SSTS AND IN LIGHT/MODERATE SHEAR...THE POOR INITIAL
STRUCTURE WILL LIKELY PREVENT HUMBERTO FROM SIGNIFICANT
STRENGTHENING IN THE SHORT TERM.  AFTER 24H...THE SYSTEM SHOULD
ACCELERATE TO THE NORTHEAST...AND MOST OF THE GUIDANCE SHOW SOME
INCREASE IN STRENGTH DURING EXTRATROPICAL TRANSITION.  AFTER
ACCOUNTING FOR THE WEAKER INITIAL WINDS...THE LATEST NHC FORECAST
IS BASICALLY AN UPDATE OF THE PREVIOUS ONE.

SINCE THE CIRCULATION HAS BECOME ELONGATED...THE INITIAL MOTION
ESTIMATE IS A VERY UNCERTAIN 010/8.  GUIDANCE REMAINS IN GOOD
AGREEMENT ON HUMBERTO TURNING TO THE NORTHEAST AND ACCELERATING
AHEAD OF A MID-LATITUDE TROUGH.  THE OFFICIAL FORECAST IS NUDGED A
LITTLE TO THE EAST CLOSER TO THE MODEL CONSENSUS.  GLOBAL MODELS
SUGGEST THE CYCLONE WILL DISSIPATE OR BE ABSORBED WITHIN A LARGER
EXTRATROPICAL LOW BY 72H.  THE NHC PREDICTION WILL GO ALONG WITH
THE ABSORBED SCENARIO...THOUGH IT WOULD NOT BE SURPRISING IF
HUMBERTO OPENED UP INTO A TROUGH BEFORE THAT TIME.

FORECAST POSITIONS AND MAX WINDS

INIT  19/0300Z 32.5N  43.4W   30 KT  35 MPH
 12H  19/1200Z 33.7N  43.0W   30 KT  35 MPH
 24H  20/0000Z 35.7N  41.6W   30 KT  35 MPH
 36H  20/1200Z 38.6N  38.8W   35 KT  40 MPH
 48H  21/0000Z 43.0N  34.5W   45 KT  50 MPH...POST-TROP/EXTRATROP
 72H  22/0000Z...ABSORBED

$$
FORECASTER BLAKE


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