WDPS31 PGTW 130900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 05P (CODY) WARNING NR 019// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 26.2S 177.0E INITIAL INTENSITY: 45 KTS GEOGRAPHIC REFERENCE: 492 NM SOUTH OF SUVA, FIJI MOVEMENT PAST 6 HOURS: EAST-SOUTHEASTWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 22 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A BROAD, INCREASINGLY RAGGED LOW LEVEL CIRCULATION CENTER (LLCC), WITH THE ONLY SIGNIFICANT CONVECTIVE ACTIVITY SHEARED WELL TO THE SOUTHEAST. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON THE EXPOSED LLCC AND AN EXTRAPOLATION OF A LOW LEVEL CIRCULATION EVIDENT IN A 130514Z SSMIS 36GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY OF 45 KNOTS IS ASSESSED WITH MEDIUM CONFIDENCE, HEDGED HIGHER THAN DVORAK CURRENT INTENSITY ESTIMATES BASED ON AN EARLIER SCATTEROMETER PASS WHICH INDICATED 45-50 KNOT WINDS SURROUNDING THE SYSTEM, AND A 130200Z AMSR2 WINDSPEED PRODUCT INDICATING A SIMILAR WIND FIELD. TROPICAL CYCLONE 05P IS A HYBRID SYSTEM RAPIDLY TRANSITIONING TO A SUBTROPICAL CYCLONE. PHASE SPACE DIAGRAMS AND AMSU THERMAL CROSS-SECTIONS INDICATE THE SYSTEM REMAINS WARM CORE, HOWEVER IT IS MOVING OVER RELATIVELY COOL WATERS BETWEEN 24-25C, AND SITS UNDER STRONG MID-LATITUDE NORTHWESTERLY FLOW ALOFT WITH STRONG VERTICAL WIND SHEAR. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A COMBINED NEAR-EQUATORIAL RIDGE (NER) AND SUBTROPICAL RIDGE (STR) COMPLEX TO THE EAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.5 - 35 KTS KNES: T2.5 - 35 KTS CIMSS SATCON: 41 KTS AT 132054Z CIMSS ADT: 25 KTS AT 130540Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE VWS: 25-30 KTS SST: 24-25 CELSIUS OUTFLOW: MODERATE POLEWARD OTHER FACTORS: DRY AIR ENTRAINMENT ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM 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 05P IS TRACKING TO THE SOUTH ALONG THE WESTERN SIDE OF A DEEP, COMPLEX RIDGE PATTERN EXTENDING SOUTHWARD FROM A NER CENTERED NEAR 10S. THE STR PORTION OF THIS COMPLEX IS EXPECTED TO BUILD AND EXTEND TOWARDS THE WEST TO THE SOUTH OF TC 05P OVER THE NEXT 12 HOURS. TC 05P WILL SLOW DOWN AS A RESULT, TO ROUGHLY HALF ITS CURRENT FORWARD SPEED. INTENSITY IS FORECAST TO REMAIN RELATIVELY STEADY THROUGH MOST OF THE FORECAST, WITH A SLIGHT WEAKENING BY THE END OF THE FORECAST PERIOD. TC 05P CURRENTLY EXHIBITS BOTH TROPICAL AND SUBTROPICAL FEATURES, AS NOTED ABOVE. AS IT CONTINUES MOVING SOUTHWARD OVER PROGRESSIVELY COOLER WATERS AND INTO AN AREA OF INCREASING VWS, IT IS EXPECTED TO TRANSITION TO A GALE-FORCE SUBTROPICAL LOW NO LATER THAN TAU 24. AFTER TAU 48, THE SYSTEM WILL TRANSITION TO A GALE-FORCE, COLD-CORE CYCLONE AS IT APPROACHES THE NORTH ISLAND OF NEW ZEALAND. MODEL DISCUSSION: NUMERICAL TRACK GUIDANCE IS IN GOOD AGREEMENT THROUGH THE FORECAST PERIOD, WITH ALL TRACKERS CLOSELY PACKED INTO A 40NM ENVELOPE, LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. INTENSITY GUIDANCE REMAINS TIGHTLY CLUSTERED ABOUT THE MEAN, LENDING HIGH CONFIDENCE TO THE INTENSITY FORECAST. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH INTENSITY 0 - 72 HR: HIGH// NNNN