[Tropical] Tropical Cyclone Discussion

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WTNT41 KNHC 310249
TCDAT1

HURRICANE KIRK DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112012
1100 PM AST THU AUG 30 2012

KIRK CONTINUES TO MAINTAIN AN IMPRESSIVE CLOUD PATTERN...WITH A
SYMMETRIC CENTRAL DENSE OVERCAST COMPRISED OF COLD CLOUD TOP
TEMPERATURES.  ALTHOUGH THE EARLIER RAPID INTENSIFICATION PHASE
SEEMS TO HAVE LEVELED OFF...THE EYE HAS WARMED FURTHER AND BECOME
BETTER DEFINED IN THE LAST FEW HOURS. DVORAK INTENSITY ESTIMATES
ARE A CONSENSUS 4.5 FROM TAFB AND SAB...BUT THE LATEST ADT VALUES
HAVE BEEN RUNNING CLOSER TO T5.0. THE INITIAL INTENSITY ESTIMATE IS
RAISED TO 85 KT IN AGREEMENT WITH A BLEND OF THESE DATA SOURCES.
KIRK HAS ANOTHER DAY OR SO TRAVERSING WARM WATERS IN A RELATIVELY
LOW SHEAR ENVIRONMENT. THE CYCLONE ALSO HAS A WELL-ESTABLISHED
OUTFLOW SINK TO THE EAST AND IS FORECAST TO APPROACH A JET TO THE
NORTHWEST...WHICH COULD SERVE AS AN ADDITIONAL OUTFLOW CHANNEL.
THESE FACTORS...ALONG WITH THE STATISTICAL-DYNAMICAL GUIDANCE...
SUGGESTS A PEAK INTENSITY OCCURRING AROUND OR JUST AFTER THE POINT
OF RECURVATURE. A SHARP INCREASE IN SHEAR AND A TRACK OVER RAPIDLY
DECREASING SEA SURFACE TEMPERATURES BEYOND 48 HOURS SHOULD RESULT
IN STEADY OR EVEN RAPID WEAKENING. A QUICK-MOVING FRONTAL ZONE
SHOULD BEGIN TO OVERTAKE KIRK IN 2-3 DAYS...RESULTING IN
EXTRATROPICAL TRANSITION JUST AROUND 72 HOURS AND ABSORPTION IN 96
HOURS.  THE NHC INTENSITY FORECAST IS NEARLY IDENTICAL TO THE
PREVIOUS ONE...AND IS SLIGHTLY HIGHER THAN THE SHIPS/LGEM INTENSITY
AIDS.

THE INITIAL MOTION ESTIMATE HAS VEERED A HAIR TO THE RIGHT AND IS
335/10. THE TRACK FORECAST IS CLEAR-CUT. KIRK HAS REACHED THE
WESTERN END OF SUBTROPICAL RIDGE TO THE EAST AND SHOULD UNDERGO
RECURVATURE IN THE NEXT 24 HOURS. THE CYCLONE SHOULD THEN GRADUALLY
BECOME EMBEDDED IN MID-LATITUDE WESTERLIES...AND ACCELERATE AT WARP
SPEED WITH THE APPROACH OF A POTENT MID-LATITUDE SHORTWAVE OVER THE
CANADIAN MARITIME PROVINCES IN 36-48 HOURS. THE NEW TRACK FORECAST
IS VIRTUALLY UNCHANGED FROM THE PREVIOUS ONE...GIVEN THE EXCELLENT
AGREEMENT IN THE NUMERICAL MODEL GUIDANCE.


FORECAST POSITIONS AND MAX WINDS

INIT  31/0300Z 29.0N  50.7W   85 KT 100 MPH
 12H  31/1200Z 30.5N  50.8W   90 KT 105 MPH
 24H  01/0000Z 33.0N  50.0W   95 KT 110 MPH
 36H  01/1200Z 35.8N  47.9W   95 KT 110 MPH
 48H  02/0000Z 38.7N  44.5W   85 KT 100 MPH
 72H  03/0000Z 46.2N  34.3W   65 KT  75 MPH...POST-TROP/EXTRATROP
 96H  04/0000Z 52.0N  20.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  05/0000Z...DISSIPATED

$$
FORECASTER KIMBERLAIN


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