WDPS32 PGTW 031500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 16P (KEVIN) WARNING NR 008// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 18.5S 168.6E INITIAL INTENSITY: 90 KTS GEOGRAPHIC REFERENCE: 51 NM SOUTH-SOUTHEAST OF PORT VILA, VANUATU MOVEMENT PAST 6 HOURS: SOUTHEASTWARD AT 13 KTS SIGNIFICANT WAVE HEIGHT: 45 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY SHOWS A LARGE SYSTEM (620NM ACROSS) THAT HAS FURTHER IMPROVED WITH DEEPENING CENTRAL CONVECTION AND THE EMERGENCE OF AN EYE FEATURE. EXPANSIVE FEEDER BANDS CONTINUE TO TRAIL FROM ALL QUADRANTS. THE INITIAL POSITION IS BASED WITH HIGH CONFIDENCE ON THE EYE IN THE EIR LOOP. THE INITIAL INTENSITY IS BASED ON THE CLOSELY-CLUSTERED AGENCY DVORAK ESTIMATES OF T5.0 AND REFLECTS THE 6-HR IMPROVEMENT. ANALYSIS INDICATES AN OVERALL FAVORABLE ENVIRONMENT WITH WARM SST, MODERATE RADIAL OUTFLOW, AND LOW VERTICAL WIND SHEAR. INITIAL WIND RADII BASIS: PERSISTENCE. CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE EAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T5.0 - 90 KTS PHFO: T5.0 - 90 KTS NFFN: T5.0 - 90 KTS CIMSS ADT: 79 KTS AT 030830Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 5-10 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE RADIAL ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC KEVIN WILL CONTINUE TO TRACK SOUTHEASTWARD UNDER THE STEERING STR. THE FAVORABLE ENVIRONMENT WILL SUSTAIN STEADY INTENSIFICATION TO A PEAK OF 100KTS BY TAU 24; AFTERWARD, INCREASING VWS AND COOLING SST WILL SLOWLY ERODE THE SYSTEM DOWN TO 45KTS BY TAU 72. CONCURRENTLY BY TAU 48, TC 16P WILL BEGIN SUBTROPICAL TRANSITION AND BY TAU 72, WILL TRANSFORM INTO A SUBTROPICAL LOW WITH AN EXPANDING WIND FIELD. MODEL DISCUSSION: THE NUMERICAL MODELS ARE IN VERY TIGHT AGREEMENT WITH A GRADUAL AND EVEN SPREAD TO 195NM BY TAU 72, LENDING HIGH CONFIDENCE TO THE JTWC TRACK FORECAST. DUE TO VARIABILITY INTRODUCED BY SUBTROPICAL TRANSITION, THERE IS OVERALL MEDIUM CONFIDENCE IN THE INTENSITY FORECAST. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH INTENSITY 0 - 72 HR: MEDIUM// NNNN