077 
 WTNT42 KNHC 182056
 TCDAT2
  
 TROPICAL STORM BRET DISCUSSION NUMBER   5
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL022011
 500 PM EDT MON JUL 18 2011
  
 VISIBLE SATELLITE IMAGERY THIS AFTERNOON SHOWED A RAGGED EYE-LIKE
 FEATURE...SUGGESTING THAT SOME INTENSIFICATION HAD TAKEN PLACE. 
 THIS WAS CONFIRMED BY OBSERVATIONS FROM THE AIR FORCE HURRICANE
 HUNTER AIRCRAFT.  USING A BLEND OF PEAK FLIGHT-LEVEL...SFMR...AND
 DROPSONDE WIND SPEED MEASUREMENTS THE CURRENT INTENSITY IS SET AT
 55 KT.  THE SHIPS MODEL OUTPUT SHOWS A SUBSTANTIAL INCREASE IN
 VERTICAL SHEAR WITHIN 12 TO 24 HOURS...SO BRET HAS A NARROW WINDOW
 OF OPPORTUNITY TO STRENGTHEN SOME MORE BEFORE REACHING A LESS
 CONDUCIVE ENVIRONMENT...AND IT COULD BE NEAR HURRICANE STRENGTH BY
 EARLY TOMORROW OR SOONER.  THE OFFICIAL FORECAST FOLLOWS THE
 INTENSITY MODEL CONSENSUS...IVCN.
 
 AIRCRAFT AND SATELLITE FIXES GIVE A MOTION ESTIMATE OF AROUND 030/6.
 THE TRACK FORECAST PHILOSOPHY HAS NOT CHANGED MUCH.  BRET SHOULD BE
 STEERED NORTH-NORTHEASTWARD TO NORTHEASTWARD AROUND THE
 NORTHWESTERN PERIPHERY OF A MID-LEVEL SUBTROPICAL HIGH OVER THE
 NEXT COUPLE OF DAYS.  LATER IN THE FORECAST PERIOD...THE CYCLONE
 SHOULD ACCELERATE SOMEWHAT TOWARD THE EAST-NORTHEAST AS IT BECOMES
 MORE EMBEDDED WITHIN HIGHER-LATITUDE WESTERLY FLOW.  THE NHC
 FORECAST FOR THIS ADVISORY IS SOMEWHAT FASTER THAN...AND SLIGHTLY
 TO THE LEFT OF...THE PREVIOUS ONE.  THIS IS RATHER CLOSE TO THE
 LATEST ECMWF TRACK.
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  18/2100Z 28.3N  77.0W   55 KT  65 MPH
  12H  19/0600Z 29.2N  76.5W   60 KT  70 MPH
  24H  19/1800Z 30.4N  75.6W   60 KT  70 MPH
  36H  20/0600Z 31.5N  74.4W   55 KT  65 MPH
  48H  20/1800Z 33.0N  72.5W   50 KT  60 MPH
  72H  21/1800Z 35.5N  67.5W   40 KT  45 MPH
  96H  22/1800Z 39.0N  60.0W   35 KT  40 MPH
 120H  23/1800Z 43.0N  52.0W   30 KT  35 MPH...POST-TROP/EXTRATROP
  
 $$
 FORECASTER PASCH