Hurricane MICHAEL Forecast Discussion Number 29

 | By Seamus on 9/10/2012 4:55:58 AM | Views (3) Issued at 500 AM AST MON SEP 10 2012

000
WTNT43 KNHC 100843
TCDAT3
 
HURRICANE MICHAEL DISCUSSION NUMBER  29
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132012
500 AM AST MON SEP 10 2012
 
ALTHOUGH DEEP CONVECTION ASSOCIATED WITH MICHAEL HAS INCREASED
RECENTLY...THE EYE APPEARS LESS DISTINCT AND IT HAS BEEN
OCCASIONALLY CLOUD FILLED. THE INITIAL WIND SPEED IS LOWERED A
LITTLE TO 70 KT...WHICH IS NEAR THE AVERAGE OF THE LATEST DVORAK
FINAL T- AND CI-NUMBERS FROM TAFB AND SAB. THE SHIPS MODEL SHOWS
ABOUT 15 KT OF NORTHERLY SHEAR AFFECTING MICHAEL CURRENTLY. THE
SHEAR IS EXPECTED TO INCREASE OVER THE NEXT DAY OR SO...WHICH
SHOULD PROMOTE ADDITIONAL WEAKENING. BY TUESDAY NIGHT...MICHAEL IS
EXPECTED TO MOVE OVER WATER TEMPERATURES WELL BELOW 26C AND BE
NEARING A COLD FRONT. THESE CONDITIONS SHOULD CAUSE CONTINUED
WEAKENING AND A TRANSITION TO A POST-TROPICAL CYCLONE. THE MODELS
ARE IN RELATIVELY GOOD AGREEMENT IN SHOWING THE POST-TROPICAL LOW
MERGING WITH THE FRONT ON WEDNESDAY. THE NHC INTENSITY FORECAST IS
NEAR THE CONSENSUS AIDS.
 
MICHAEL HAS BEEN MOVING SOUTH OF DUE WEST FOR THE PAST 12 HOURS OR
SO...AND THE LATEST INITIAL MOTION ESTIMATE IS 265/6. A TURN TO THE
WEST-NORTHWEST IS EXPECTED LATER TODAY FOLLOWED BY A FASTER
NORTHWESTWARD MOTION TONIGHT...AS MICHAEL MOVES TO THE SOUTHWESTERN
PORTION OF A MID-LEVEL RIDGE. IN 24 TO 48 HOURS...THE CYCLONE IS
EXPECTED TO BE EMBEDDED IN STRONG FLOW BETWEEN THE AFOREMENTIONED
RIDGE AND A HIGH AMPLITUDE TROUGH. THIS FLOW PATTERN SHOULD CAUSE
MICHAEL...OR THE POST-TROPICAL CYCLONE...TO ACCELERATE NORTHWARD OR
NORTH-NORTHEASTWARD UNTIL IT IS ABSORBED. THE NHC TRACK FORECAST IS
SIMILAR TO THE GFS AND ECMWF SOLUTIONS.
 
THE 34-KT AND 50-KT WIND RADII WERE ADJUSTED BASED ON AN ASCAT PASS
SHORTLY AFTER 0000 UTC.

FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0900Z 33.5N  45.2W   70 KT  80 MPH
 12H  10/1800Z 34.0N  46.5W   65 KT  75 MPH
 24H  11/0600Z 36.0N  47.9W   55 KT  65 MPH
 36H  11/1800Z 39.1N  47.6W   45 KT  50 MPH
 48H  12/0600Z 43.5N  45.0W   40 KT  45 MPH...POST-TROPICAL
 72H  13/0600Z...DISSIPATED
 
$$
FORECASTER CANGIALOSI
 

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