Hurricane HILARY

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HURRICANE HILARY DISCUSSION NUMBER   7
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092011
200 PM PDT THU SEP 22 2011
 
HILARY HAS STRENGTHENED RAPIDLY THROUGHOUT THE DAY. THE EYE FIRST
APPEARED IN SATELLITE IMAGES AROUND 1500 UTC...AND IT HAS MORE
DISTINCT SINCE THAT TIME. CLOUD TOPS ARE AS COLD AS -80C TO THE
NORTH OF THE EYE...AND THE OVERALL CONVECTIVE PATTERN HAS BECOME
MORE SYMMETRIC DURING THE PAST FEW HOURS. DVORAK CLASSIFICATIONS
HAVE INCREASED AND NOW SUPPORT AN INITIAL WIND SPEED OF 90 KT...AND
THAT COULD BE CONSERVATIVE. HILARY WILL LIKELY STRENGTHEN FURTHER
DURING THE NEXT 24 HOURS OR SO AS IT REMAINS IN A CONDUCIVE
ENVIRONMENT. BY THE END OF THE FORECAST PERIOD...VERTICAL WIND
SHEAR COULD INCREASE OVER THE HURRICANE AS IT MOVES INTO A LESS
FAVORABLE THERMODYNAMIC ENVIRONMENT. THE OFFICIAL FORECAST CLOSELY
FOLLOWS THE SHIPS...LGEM...AND FLORIDA STATE SUPERENSEMBLE MODELS
AND IS HIGHER THAN THE PREVIOUS FORECAST.

HILARY HAS WOBBLED A LITTLE TO THE NORTH OF THE PREVIOUS TRACK...AND
THE LATEST INITIAL MOTION ESTIMATE IS 300/9.  MID-LEVEL RIDGING IS
EXPECTED TO STRENGTHEN TO THE NORTH OF THE HURRICANE DURING THE
NEXT FEW DAYS. THIS PATTERN SHOULD STEER HILARY WEST-NORTHWESTWARD
DURING THAT TIME.  BY THE END OF THE PERIOD...THERE IS A
SIGNIFICANT SPREAD IN THE MODELS WITH THE REGIONAL HURRICANE
MODELS SHOWING A SHARP NORTHWARD TURN WHILE MOST OF THE GLOBAL
MODELS KEEP HILARY ON A MORE STRAIGHT WESTWARD PATH.  OVERALL...THE
OFFICIAL FORECAST HAS BEEN NUDGED TO THE SOUTH LATE IN THE FORECAST
PERIOD...LEANING TOWARD THE GLOBAL MODELS. 

AN ASCAT OVERPASS AT 1644 UTC INDICATE THAT THE WIND RADII REMAIN
QUITE SMALL.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/2100Z 15.6N  99.8W   90 KT 105 MPH
 12H  23/0600Z 16.1N 101.1W  110 KT 125 MPH
 24H  23/1800Z 16.5N 102.8W  115 KT 135 MPH
 36H  24/0600Z 16.8N 104.5W  115 KT 135 MPH
 48H  24/1800Z 17.1N 106.2W  110 KT 125 MPH
 72H  25/1800Z 18.0N 109.4W  105 KT 120 MPH
 96H  26/1800Z 19.0N 112.0W   95 KT 110 MPH
120H  27/1800Z 19.5N 113.5W   85 KT 100 MPH
 
$$
FORECASTER CANGIALOSI/PASCH
 
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