000
WTPZ44 KNHC 220242
TCDEP4
 
TROPICAL STORM HILARY DISCUSSION NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092011
800 PM PDT WED SEP 21 2011
 
THE CLOUD PATTERN HAS CONTINUED TO CONSOLIDATE AND DEEP CONVECTION
HAS INCREASED NEAR THE CENTER. IN FACT...MICROWAVE DATA DURING THE
AFTERNOON AND EARLY EVENING REVEAL A DISTINCT RING OF DEEP
CONVECTION INDICATING THAT THE INNER CORE IS BECOMING BETTER
ORGANIZED. T-NUMBERS FROM BOTH TAFB AND SAB HAVE INCREASED TO 3.0
YIELDING AN INITIAL INTENSITY OF 45 KNOTS. GIVEN THE LOW SHEAR AND
THE WARM OCEAN...STRENGTHENING IS INDICATED AND HILARY IS EXPECTED
TO BECOME A HURRICANE BY THURSDAY WITH THE GOOD POSSIBILITY OF
RAPID INTENSIFICATION.  THE OFFICIAL FORECAST FOLLOWS VERY CLOSE
THE STATISTICAL LGEM MODEL BUT IS NOT AS AGGRESSIVE AS THE HWRF.

HILARY IS MOVING TOWARD THE WEST-NORTHWEST AT ABOUT 6 KNOTS. THE
STEERING CURRENTS ARE WEAK BUT MOST OF THE GLOBAL MODELS GRADUALLY
BUILD THE SUBTROPICAL RIDGE TO THE NORTH OF THE CYCLONE. THIS
PATTERN SHOULD FAVOR A CONTINUATION OF THE WEST-NORTHWESTWARD MOTION
WITH A SLIGHT INCREASE IN FORWARD SPEED. WITH THE EXCEPTION OF THE
HWRF/GFDL PAIR WHICH TURNS HILARY NORTHWARD TOWARD BAJA CALIFORNIA
OR THE GULF OF CORTES BY THE END OF THE FORECAST PERIOD...THE REST
OF THE GUIDANCE KEEPS HILARY ON A GENERAL WEST-NORTHWEST TRACK
THROUGH FIVE DAYS AND SO DOES THE OFFICIAL FORECAST.

GIVEN THE GOOD PROSPECTS FOR INTENSIFICATION...A TRACK NOT TOO FAR
TO THE SOUTHWEST COAST OF MEXICO...AND THE WIND RADII...A TROPICAL
STORM WARNING HAS BEEN ISSUED FOR A PORTION OF THE COAST. 
  
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/0300Z 14.4N  97.2W   45 KT  50 MPH
 12H  22/1200Z 14.7N  98.0W   55 KT  65 MPH
 24H  23/0000Z 15.2N  99.5W   65 KT  75 MPH
 36H  23/1200Z 15.8N 101.5W   75 KT  85 MPH
 48H  24/0000Z 16.5N 103.5W   80 KT  90 MPH
 72H  25/0000Z 18.0N 107.0W   90 KT 105 MPH
 96H  26/0000Z 18.5N 110.5W   90 KT 105 MPH
120H  27/0000Z 19.0N 113.5W   80 KT  90 MPH
 
$$
FORECASTER AVILA