WDPS31 PGTW 022100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 15P (JUDY) WARNING NR 016// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 25.0S 176.4E INITIAL INTENSITY: 80 KTS GEOGRAPHIC REFERENCE: 429 NM SOUTH-SOUTHWEST OF SUVA, FIJI MOVEMENT PAST 6 HOURS: EAST-SOUTHEASTWARD AT 17 KTS SIGNIFICANT WAVE HEIGHT: 39 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: AS THE FIRST FEW HOURS OF DAYLIGHT REACH THE CORAL SEA, ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC). A 021542Z SSMIS 89GHZ COLOR COMPOSITE MICROWAVE IMAGE REVEALS THE WESTERN PORTION OF 15P HAS BEEN COMPROMISED BY DRY AIR ENTRAINMENT. THE SINGULAR VERTICAL HOT TOWER IS EAST OF THE LLCC AS THE LEADING EDGE OF THE SYSTEM BEGINS TO INTERACT WITH THE SUBTROPICAL JET ALOFT. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON MSI AND SSMIS IMAGERY. THE INITIAL INTENSITY OF 80 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON AN AGREEMENT BETWEEN AGENCY DVORAK INTENSITY ESTIMATES AND AUTOMATED ESTIMATES LIKE CIMSS SATCON WHICH ALL INDICATE 77-90KTS WHILE ESTIMATES LIKE CIMSS ADT REMAIN LOWER. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.5 - 77 KTS KNES: T5.0 - 90 KTS PHFO: T5.0 - 90 KTS CIMSS SATCON: 92 KTS AT 021319Z CIMSS ADT: 67 KTS AT 021730Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE VWS: 30+ KTS SST: 26-27 CELSIUS OUTFLOW: STRONG EASTWARD ANALYSIS CONFIDENCE: INITIAL POSITION: MEDIUM INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 15P (JUDY) IS FORECAST TO CONTINUE TRACKING EAST-SOUTHEASTWARD UNDER THE STEERING INFLUENCE OF THE STR. THE UNFAVORABLE ENVIRONMENT CHARACTERIZED BY HIGH VERTICAL WIND SHEAR, INCREASING DRY AIR ENTRAINMENT AND COOLING SEA SURFACE TEMPERATURES WILL GRADUALLY ERODE THE SYSTEM DOWN TO 55KTS BY TAU 24. ALREADY POLEWARD OF THE 26C ISOTHERM, THE INCREASING INTERACTION WITH THE SUBTROPICAL JET AND BAROCLINIC ZONE WILL BEGIN SUBTROPICAL TRANSITION (STT). BY TAU 36, 15P WILL TRANSFORM INTO A SUBTROPICAL LOW WITH AN EXPANDING WIND FIELD. MODEL DISCUSSION: NUMERICAL MODELS ARE IN TIGHT AGREEMENT THAT 15P WILL TRAVEL EAST-SOUTHEASTWARD UNTIL EVENTUAL STT NEAR TAU 36. FOR THIS REASON THE JTWC FORECAST TRACK IS PLACED WITH HIGH CONFIDENCE. RELIABLE MODEL INTENSITY GUIDANCE IS IN GOOD AGREEMENT WITH ALL MEMBERS QUICKLY WEAKENING THE SYSTEM THROUGH THE FORECAST PERIOD. FOR THIS REASON THE JTWC INTENSITY FORECAST IS PLACED WITH MEDIUM CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH INTENSITY 0 - 72 HR: MEDIUM// NNNN