342 
 WTPZ45 KNHC 041436
 TCDEP5
  
 HURRICANE EUGENE DISCUSSION NUMBER  18
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP052011
 800 AM PDT THU AUG 04 2011
  
 COLDER CLOUD TOPS DEVELOPED AROUND THE EYE SEVERAL HOURS AGO...AND
 SUBJECTIVE DVORAK CURRENT INTENSITY ESTIMATES AT 1200 UTC WERE 115
 KT AND 102 KT FROM TAFB AND SAB...RESPECTIVELY.  IN ADDITION...
 OBJECTIVE ADT ESTIMATES FROM UW-CIMSS INCREASED BACK UP TO 115 KT
 AFTER 0800 UTC.  A BLEND OF THESE NUMBERS SUGGESTS AN INITIAL
 INTENSITY OF 105 KT.
  
 THE INITIAL MOTION IS STILL 285/12 AND SHOULD REMAIN ESSENTIALLY
 UNCHANGED FOR THE NEXT 48 HOURS AS EUGENE CONTINUES TO BE STEERED
 BY THE MID-LEVEL RIDGE...WHOSE AXIS IS ALONG 28N.  THE TRACK
 GUIDANCE HAS SHIFTED A LITTLE TO THE SOUTH...AND THE NEW OFFICIAL
 FORECAST LIES CLOSE TO THE MULTI-MODEL CONSENSUS TVCE.  EUGENE
 SHOULD SLOW DOWN BY DAYS 3 AND 4 AS THE WEAKENED CYCLONE IS STEERED
 BY WEAK LOW-LEVEL FLOW.
 
 FOR THE FIRST TIME...THE SHIPS-DERIVED ANNULAR HURRICANE INDEX
 INDICATES THAT EUGENE HAS GAINED ANNULAR CHARACTERISTICS...AND THE
 SLOW WEAKENING OVER THE PAST 18 HOURS OR SO BEARS THIS OUT. 
 TRUTHFULLY...THE PRESENTATION OF THE HURRICANE HAS DEGRADED SOMEWHAT
 IN THE LAST FEW INFRARED AND MICROWAVE SATELLITE IMAGES...BUT IT
 WILL TAKE A LITTLE TIME FOR THE DVORAK CI NUMBERS...AND PRESUMABLY
 THE ACTUAL INTENSITY...TO DECREASE.  ALSO...SINCE THE FORECAST
 TRACK HAS SHIFTED A LITTLE SOUTH...THE SEA SURFACE TEMPERATURES
 ALONG THE TRACK WILL BE DECREASING MORE GRADUALLY AND COULD SUPPORT
 SLOWER WEAKENING.  IN LIGHT OF THESE POINTS...THE OFFICIAL
 INTENSITY FORECAST IS A BIT HIGHER THAN ALL THE GUIDANCE FOR THE
 FIRST 12 HOURS AND THEN FOLLOWS THE HIGHEST OF THE MODELS...THE
 LGEM...FOR THE REST OF THE FORECAST PERIOD.  EUGENE SHOULD
 ULTIMATELY WEAKEN TO A REMNANT LOW BY DAY 4 OVER 22C DEGREE WATERS
 AND DEGENERATE TO A TROUGH BY DAY 5...AS INDICATED IN THE GLOBAL
 MODEL FIELDS.
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  04/1500Z 16.8N 118.9W  105 KT 120 MPH
  12H  05/0000Z 17.4N 120.8W   90 KT 105 MPH
  24H  05/1200Z 18.0N 123.2W   70 KT  80 MPH
  36H  06/0000Z 18.6N 125.6W   55 KT  65 MPH
  48H  06/1200Z 19.2N 127.8W   45 KT  50 MPH
  72H  07/1200Z 20.5N 131.5W   30 KT  35 MPH
  96H  08/1200Z 21.0N 134.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
 120H  09/1200Z...DISSIPATED
  
 $$
 FORECASTER BERG