000 WTPZ41 KNHC 041451 TCDEP1 HURRICANE HENRIETTE DISCUSSION NUMBER 20 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP112007 800 AM PDT TUE SEP 04 2007 HENRIETTE HAS BEEN STRENGTHENING THIS MORNING WITH A DISTINCT EYE NOW APPARENT IN BOTH CONVENTIONAL SATELLITE IMAGERY AND RADAR DATA FROM CABO SAN LUCAS. THE INITIAL INTENSITY IS INCREASED TO 75 KT BASED ON DVORAK INTENSITY ESTIMATES OF 75 KT FROM BOTH TAFB AND SAB. HENRIETTE IS MOVING A LITTLE FASTER THAN BEFORE WITH THE INITIAL MOTION ESTIMATED AT 335/9. THE FORECAST REASONING REMAINS ESSENTIALLY THE SAME. THE CYCLONE IS EXPECTED TO TURN NORTHWARD WITH A SLIGHT ACCELERATION IN FORWARD SPEED AHEAD OF A TROUGH CURRENTLY SITUATED ALONG THE WEST COAST OF THE UNITED STATES. THE MODEL GUIDANCE REMAINS CLUSTERED ABOUT A TRACK OVER THE SOUTHERN BAJA PENINSULA DURING THE NEXT 12-24 HOURS...THEN CROSSING THE SEA OF CORTEZ AND REACHING THE MAINLAND COAST OF MEXICO IN ABOUT 36 HOURS. THE UKMET MODEL CONTINUES TO BE ALONG THE EAST SIDE OF THE MODEL GUIDANCE SUITE WHILE THE GFDL IS SURPRISINGLY LOCATED TOWARD THE LEFT SIDE OF THE GUIDANCE ENVELOPE. THE OFFICIAL FORECAST IS BASED ON A COMPROMISE BETWEEN THESE TWO MODELS AND REPRESENTS ONLY A SMALL CHANGE TO THE PREVIOUS ADVISORY. THERE IS A SMALL OPPORTUNITY FOR A LITTLE ADDITIONAL STRENGTHENING AS HENRIETTE HAS ABOUT 6-12 HOURS OVER WATER PRIOR TO MAKING LANDFALL OVER THE SOUTHERN BAJA PENINSULA LATER TODAY. THEREAFTER...HENRIETTE IS EXPECTED TO GRADUALLY WEAKEN DUE TO LAND INTERACTION WITH THE BAJA PENINSULA AND ULTIMATELY THE HIGHLY MOUNTAINOUS TERRAIN OF MAINLAND MEXICO. HENRIETTE'S SURFACE CIRCULATION SHOULD RAPIDLY DISSIPATE ONCE INLAND OVER NORTHWESTERN MEXICO. HOWEVER...MOISTURE FROM THE REMNANTS OF HENRIETTE COULD MAKE IT INTO THE SOUTHWESTERN UNITED STATES IN 2-3 DAYS. SEVERAL CHANGES TO THE WATCH AND WARNING AREAS WERE REQUIRED FOR THIS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 04/1500Z 22.2N 109.4W 75 KT 12HR VT 05/0000Z 23.6N 110.1W 65 KT...INLAND OVER BAJA 24HR VT 05/1200Z 25.5N 110.6W 60 KT 36HR VT 06/0000Z 27.4N 110.7W 55 KT 48HR VT 06/1200Z 29.2N 110.5W 40 KT...INLAND 72HR VT 07/1200Z...DISSIPATED $$ FORECASTER RHOME