000
WTPZ41 KNHC 040250
TCDEP1
TROPICAL STORM HENRIETTE DISCUSSION NUMBER  18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP112007
800 PM PDT MON SEP 03 2007
 
RECENT MICROWAVE IMAGERY AND RADAR DATA FROM CABO SAN LUCAS SUGGEST
THAT A BANDING TYPE EYE HAS BEEN TRYING TO FORM.  HOWEVER...THE
OVERALL SATELLITE APPEARANCE HAS DEGRADED THIS EVENING WITH THE
CONVECTIVE CLOUD TOPS WARMING SINCE THE AIR FORCE HURRICANE HUNTER
AIRCRAFT SAMPLED THE CYCLONE THIS AFTERNOON. DVORAK DATA T NUMBERS
FROM TAFB AND SAB SUPPORT 65 AND 55 KT RESPECTIVELY...THEREFORE THE
INITIAL INTENSITY WILL REMAIN 60 KT.

THE INITIAL MOTION ESTIMATE IS 325/6....WHICH IS A LITTLE TO THE
RIGHT OF THE PREVIOUS ADVISORY.  THE OVERALL FORECAST PHILOSOPHY
REMAINS UNCHANGED WITH THE CYCLONE FORECAST TO TURN NORTHWARD
AHEAD OF A TROUGH THAT IS CURRENTLY NEARING THE WEST COAST OF THE
UNITED STATES.  THE MODELS REMAIN FAIRLY TIGHTLY CLUSTERED THROUGH
48 HOURS...BUT THEY HAVE SHIFTED A LITTLE EASTWARD.  THE
GFDL...UKMET AND THE FLORIDA STATE SUPERENSEMBLE ARE ALONG THE
EASTERN EDGE OF THE GUIDANCE.  THE OFFICIAL FORECAST HAS BEEN
ADJUSTED A LITTLE EASTWARD NEAR THE MODEL CONSENSUS.  THE NHC
FORECAST INDICATES THAT HENRIETTE WILL BE NEAR OR OVER THE SOUTHERN
BAJA PENINSULA IN ABOUT 24 HOURS.  THEREAFTER...HENRIETTE IS
EXPECTED TO REEMERGE OVER THE GULF OF CALIFORNIA BEFORE MAKING A
FINAL LANDFALL IN NORTHWESTERN MEXICO IN A COUPLE OF DAYS.  IT IS
IMPORTANT TO NOT FOCUS ON THE EXACT FORECAST TRACK...SINCE THE
LONG-TERM MEAN NHC TRACK ERROR IS ABOUT 55 N MI AT 24 HOURS AND 80
N MI AT 36 HOURS.

THE INTENSITY GUIDANCE CONTINUES TO FORECAST STRENGTHENING EVEN
THOUGH HENRIETTE HAS REFUSED TO DO SO DURING THE PAST COUPLE OF
DAYS.  THE OFFICIAL FORECAST SHOWS MODEST STRENGTHENING PRIOR TO
THE CYCLONE REACHING THE BAJA PENINSULA.  THEREAFTER... WEAKENING
IS EXPECTED DUE TO LAND INTERACTION.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      04/0300Z 20.6N 108.8W    60 KT
 12HR VT     04/1200Z 21.6N 109.5W    65 KT
 24HR VT     05/0000Z 23.2N 110.1W    70 KT...NEAR BAJA PENINSULA
 36HR VT     05/1200Z 24.9N 110.7W    55 KT...NEAR EAST COAST BAJA
 48HR VT     06/0000Z 26.7N 110.8W    55 KT...OVER GULF OF CALIF
 72HR VT     07/0000Z 30.5N 109.9W    25 KT...DISSIPATING INLAND
 96HR VT     08/0000Z...DISSIPATED
 
$$
FORECASTER BROWN