ZCZC MIATCDEP3 ALL TTAA00 KNHC DDHHMM HURRICANE GEORGETTE DISCUSSION NUMBER 7 NATIONAL WEATHER SERVICE MIAMI FL 2 PM PDT WED AUG 12 1998 GEORGETTE IS A GOOD EXAMPLE OF A BANDING-TYPE HURRICANE. THE SYSTEM HAS A LARGE ENVELOPE AS INDICATED BY SATELLITE IMAGERY AND SURFACE SHIP REPORTS. A SHIP LOCATED ABOUT 205 NMI NORTHEAST OF THE CENTER ...ID KGTI...REPORTED AN E WIND OF 20 KNOTS AND SEAS OF 16 FT. BASED ON THIS DATA THE TROPICAL STORM-FORCE WIND AND 12-FOOT SEA RADII HAS BEEN MODIFIED. DVORAK INTENSITY ESTIMATES FROM TAFB AND SAB ARE IN AGREEMENT... AND THE INITIAL INTENSITY IS INCREASED TO 70 KNOTS FOR THIS ADVISORY. WITH WELL-ESTABLISHED OUTFLOW AND NO OBVIOUS FACTORS TO HINDER DEVELOPMENT...GEORGETTE IS FORECAST TO GRADUALLY STRENGTHEN THROUGH 24 HOURS. THEREAFTER...A GRADUAL WEAKENING TREND SHOULD BEGIN AS THE SYSTEM APPROACHES PROGRESSIVELY COOLER WATERS...NEAR 22 DEG C BY 72 HOURS. GEORGETTE HAS CONTINUED ON A NORTHWEST HEADING THROUGH THE DAY. THE INITIAL MOTION ESTIMATE IS 310/11 KNOTS. THE MID- TO UPPER- LEVEL LOW POSITIONED ABOUT 450 NMI NORTH OF GEORGETTE CONTINUES TO MOVE WESTWARD WITH A RIDGE BUILDING TO ITS EAST. THIS SYSTEM IS HAVING LITTLE IMPACT ON THE HURRICANE...PER WATER VAPOR IMAGERY ...AND IS FORECAST TO WEAKEN. THE 18Z TRACK MODEL GUIDANCE IS MORE TIGHTLY CLUSTERED AROUND A GENERAL NORTHWEST TRACK MOTION. THE OFFICIAL TRACK FORECAST SHOWS THIS SCENARIO...AND IS IN CLOSE AGREEMENT WITH BAM DEEP AND NHC91. GUINEY FORECAST POSITIONS AND MAX WINDS INITIAL 12/2100Z 15.1N 113.8W 70 KTS 12HR VT 13/0600Z 16.1N 115.1W 85 KTS 24HR VT 13/1800Z 17.6N 117.0W 100 KTS 36HR VT 14/0600Z 18.9N 118.8W 90 KTS 48HR VT 14/1800Z 20.5N 121.0W 75 KTS 72HR VT 15/1800Z 23.0N 125.5W 55 KTS NNNN