ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM HURRICANE DARBY DISCUSSION NUMBER 22 NATIONAL WEATHER SERVICE MIAMI FL 8 AM PDT TUE JUL 28 1998 DARBY HAS CONTINUED TO WEAKEN THIS MORNING WITH CONVECTION HAVING DECREASED IN BOTH COVERAGE AND INTENSITY. MOREOVER...THE EYE IS NO LONGER DISCERNIBLE IN INFRARED SATELLITE PICTURES. THE INITIAL INTENSITY IS DECREASED TO 85 KNOTS FOR THIS ADVISORY IN LINE WITH DVORAK INTENSITY ESTIMATES FROM TAFB AND SAB. THE INTENSITY FORECAST IS VERY SIMILAR TO THE PREVIOUS PACKAGE WITH GRADUAL WEAKENING THROUGH THE PERIOD AS THE SYSTEM ENCOUNTERS COOLER WATERS AND INCREASING SOUTHWESTERLY VERTICAL SHEAR. THE STRONGER UPPER-LEVEL SOUTH/SOUTHWESTERLY FLOW IS EVIDENT NEAR 140W IN SATELLITE IMAGERY...AND ANALYSES BY THE COOPERATIVE INSTITUTE FOR METEOROLOGICAL SATELLITE STUDIES. THE INITIAL MOTION ESTIMATE IS 285/14 KNOTS. THE OFFICIAL FORECAST TRACK CONTINUES A GENERAL WEST-NORTHWEST MOTION THROUGH THE PERIOD ...AND IS SLIGHTLY TO THE RIGHT OF THE PREVIOUS ADVISORY. DARBY SHOULD BE CROSSING 140W WITHIN THE NEXT 24 HOURS...BRINGING IT INTO THE CENTRAL PACIFIC HURRICANE CENTER AREA OF RESPONSIBILITY. GUINEY/LAWRENCE FORECAST POSITIONS AND MAX WINDS INITIAL 28/1500Z 18.1N 136.6W 85 KTS 12HR VT 29/0000Z 18.7N 138.7W 80 KTS 24HR VT 29/1200Z 19.5N 141.4W 70 KTS 36HR VT 30/0000Z 20.7N 144.0W 60 KTS 48HR VT 30/1200Z 22.0N 146.5W 50 KTS 72HR VT 31/1200Z 24.5N 151.0W 40 KTS NNNN