509 
 WTNT44 KNHC 101432
 TCDAT4
  
 TROPICAL STORM SEAN DISCUSSION NUMBER  10
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL192011
 1000 AM EST THU NOV 10 2011
  
 THERE HAS NOT BEEN MUCH CHANGE WITH SEAN OVER THE PAST SEVERAL
 HOURS. THE STORM CONTINUES TO SHOW A RAGGED EYE...WITH A MORE
 COMPACT APPEARANCE ON SATELLITE THAN YESTERDAY. DVORAK ESTIMATES
 REMAIN THE SAME...SO THE INITIAL WIND SPEED WILL REMAIN AT 55 KT.
 AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT IS SCHEDULED TO BE IN
 THE CYCLONE AROUND 1800 UTC TO PROVIDE A BETTER ESTIMATE OF THE
 INITIAL WINDS. SEAN STILL HAS A DAY OR SO OF MARGINAL WATER
 TEMPERATURES AND MODERATE SHEAR LEFT TO INTENSIFY. SOUTHWESTERLY
 SHEAR SHOULD NOTABLY INCREASE AFTER THAT TIME...WHICH SHOULD CAUSE
 WEAKENING OF THE STORM. MODEL GUIDANCE IS A LITTLE LOWER THAN SIX
 HOURS AGO...AND THE NHC FORECAST IS REDUCED FROM THE PREVIOUS ONE.
 SEAN COULD STILL BECOME A HURRICANE...ALTHOUGH IT IS NOT EXPLICITLY
 FORECAST.
  
 THE STORM HAS MADE THE TURN TO THE NORTHEAST...MOVING ABOUT 035/6.
 GUIDANCE IS IN GOOD AGREEMENT ON THIS TRACK CONTINUING WITH A
 SIGNIFICANT INCREASE IN FORWARD SPEED BY FRIDAY MORNING DUE TO AN
 APPROACHING MID-LATITUDE TROUGH.  THE NEW FORECAST IS BASICALLY AN
 UPDATE OF THE PREVIOUS ONE...SHOWING THE CYCLONE PASSING A FAIR
 DISTANCE NORTHWEST OF BERMUDA.  STRONG SHEAR...COOLER WATERS...AND
 A COLD FRONT ARE EXPECTED TO CAUSE EXTRATROPICAL TRANSITION IN
 ABOUT 36 HOURS...WITH SEAN BECOMING ABSORBED BY THAT FRONT WITHIN
 48 HOURS.  IT WOULD NOT BE SURPRISING IF SEAN DISSIPATED A LITTLE
 FASTER THAN SHOWN BELOW...AS INDICATED BY THE GFS AND UKMET MODELS.
   
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  10/1500Z 30.4N  70.5W   55 KT  65 MPH
  12H  11/0000Z 31.8N  69.0W   60 KT  70 MPH
  24H  11/1200Z 34.7N  65.6W   60 KT  70 MPH
  36H  12/0000Z 39.0N  60.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
  48H  12/1200Z...ABSORBED
  
 $$
 FORECASTER BLAKE