WTPS31 PGTW 191500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 05P (YASA) WARNING NR 029// RMKS/ 1. TROPICAL CYCLONE 05P (YASA) WARNING NR 029 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 191200Z --- NEAR 22.1S 177.8W MOVEMENT PAST SIX HOURS - 165 DEGREES AT 07 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING SUBTROPICAL RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT REPEAT POSIT: 22.1S 177.8W --- FORECASTS: 12 HRS, VALID AT: 200000Z --- 23.0S 177.7W MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING SUBTROPICAL RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 07 KTS --- 24 HRS, VALID AT: 201200Z --- 24.1S 178.5W MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING SUBTROPICAL RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 215 DEG/ 07 KTS --- 36 HRS, VALID AT: 210000Z --- 25.2S 179.3W MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY SUBTROPICAL RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT --- REMARKS: 191500Z POSITION NEAR 22.3S 177.8W. 19DEC20. TROPICAL CYCLONE 05P (YASA), LOCATED APPROXIMATELY 322 NM SOUTHEAST OF SUVA, FIJI, HAS TRACKED SOUTH-SOUTHEASTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANMIATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY SHOWS THAT THE HIGH VWS IS BEGINNING TO TAKE ITS TOLL ON TC 05P, WITH THE PREVIOUSLY FLARING CONVECTION NOW BEING SHEARED WELL TO THE SOUTHEAST OF THE PARTIALLY EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON AN EXTRAPOLATION OF A WELL DEFINED CIRCULATION IN A 190912Z ASCAT-B PASS AND A WELL DEFINED LOW EMISSIVITY REGION IN A 191050Z GPM 37GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY IS ASSESSED AT 50 KNOTS WITH HIGH CONFIDENCE, HEDGED SLIGHTLY HIGHER THAN MULTI-AGENCY DVORAK INTENSITY ESIMATES OF T3.0 FROM PGTW AND KNES, IN LIGHT OF THE PREVIOUSLY MENTIONED ASCAT PASS WHICH INDICATED 50-55 KNOT WINDS TO THE SOUTH AND SOUTHWEST OF THE LLCC. TC O5P IS MOVING GENERALLY SOUTHWARDS ALONG THE WESTERN PERIPHERY OF A DEEP STR LOCATED TO THE EAST AND IS FORECAST TO SHIFT TO A MORE SOUTHWESTWARD TRACK OVER THE NEXT 12-24 HOURS AS THE LEVEL OF THE STEERING FLOW BECOMES PROGRESSIVELY LOWER AFTER THE SYSTEM BECOMES DECAPITATED DUE TO THE HIGH VWS ASSOCIATED WITH A FINGER OF THE JET STREAM AHEAD OF AN APPROACHING UPPER-LEVEL TROUGH. BY TAU 36, TC 05P WILL BECOME FULLY EMBEDDED WITHIN THE TROUGH, AND COMPLETE TRANSITION TO A STRONG SUBTROPICAL LOW. NUMERICAL MODEL GUIDANCE IS IS GOOD AGREEMENT THROUGH THE DURATION OF THE FORECAST, HOWEVER THEY ARE NOT CAPTURING THE PREVIOUS SIX HOUR MOVEMENT TOWARDS TO THE SOUTH-SOUTHEAST. IN LIGHT OF THE RECENT MOVEMENT, THE JTWC TRACK LIES TO THE EAST OF ALL THE AVAILABLE GUIDANCE AT TAU 12, THEN HUGS THE EASTERN EDGE OF THE GUIDANCE ENVELOPE THROUGH THE REMAINDER OF THE FORECAST PERIOD WITH FAIR CONFIDENCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 191200Z IS 20 FEET. NEXT WARNINGS AT 192100Z, 200300Z, 200900Z AND 201500Z.// NNNN