ZCZC MIATCDEP4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM CELIA DISCUSSION NUMBER 8 NATIONAL WEATHER SERVICE MIAMI FL 2 AM PDT SUN JUL 19 1998 CELIA HAS LOST MOST OF ITS DEEP CONVECTION THE LAST SEVERAL HOURS. SST ANALYSIS SHOWS THAT THE SYSTEM IS ENTERING 24-25C WATERS. DVORAK INTENSITY ESTIMATES FROM BOTH TAFB AND SAB INDICATE THAT CELIA IS ON A WEAKENING TREND WITH T-NUMBERS OF 2.5 AND 3.0 RESPECTIVELY. THUS...THE INTENSITY WILL BE LOWERED TO 40 KNOTS FOR THIS ADVISORY. GRADUAL WEAKENING SHOULD CONTINUE WITH THE SYSTEM EXPECTED TO DISSIPATE WITHIN 48 HOURS. SATELLITE IMAGERY OVER THE LAST SEVERAL HOURS SHOWS THAT CELIA HAS BEEN MOVING ON A MORE WESTERLY HEADING. THIS IS CONFIRMED BY 06Z TAFB AND SAB FIX LOCATIONS. THE INITIAL MOTION ESTIMATE IS 275/10 KNOTS. THE TRACK MODEL GUIDANCE THAT RELY ON AVIATION MODEL FIELDS ...WHICH CONTINUE A WEST-NORTHWEST MOTION THROUGH 72 HOURS...ARE CONSIDERED SUSPECT DUE TO THE SPURIOUS VORTEX SOUTHWEST OF CELIA. THE OFFICIAL FORECAST TRACK CALLS FOR A GENERAL WESTWARD MOTION THROUGH 48 HOURS. THIS IS IN CLOSEST AGREEMENT WITH CLIPER... NOGAPS AND UKMET GUIDANCE AND IS CONSISTENT WITH LOWER TROPOSPHERIC STEERING. GUINEY FORECAST POSITIONS AND MAX WINDS INITIAL 19/0900Z 22.0N 115.1W 40 KTS 12HR VT 19/1800Z 22.1N 116.6W 35 KTS 24HR VT 20/0600Z 22.3N 118.7W 30 KTS 36HR VT 20/1800Z 22.4N 120.8W 25 KTS 48HR VT 21/0600Z 22.5N 122.7W 20 KTS...DISSIPATING 72HR VT 22/0600Z DISSIPATED NNNN