WTPS32 PGTW 310300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 16P (SIXTEEN) WARNING NR 002// RMKS/ 1. TROPICAL CYCLONE 16P (SIXTEEN) WARNING NR 002 03 ACTIVE TROPICAL CYCLONES IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 310000Z --- NEAR 11.9S 172.7E MOVEMENT PAST SIX HOURS - 095 DEGREES AT 16 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT REPEAT POSIT: 11.9S 172.7E --- FORECASTS: 12 HRS, VALID AT: 311200Z --- 13.0S 175.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 130 DEG/ 16 KTS --- 24 HRS, VALID AT: 010000Z --- 15.1S 178.1E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 180 NM SOUTHWEST QUADRANT 150 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 145 DEG/ 16 KTS --- 36 HRS, VALID AT: 011200Z --- 17.7S 179.9W MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 230 NM SOUTHEAST QUADRANT 180 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 155 DEG/ 16 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 020000Z --- 20.6S 178.4W MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 220 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 155 DEG/ 16 KTS --- 72 HRS, VALID AT: 030000Z --- 26.3S 175.5W MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 310300Z POSITION NEAR 12.2S 173.5E. 31JAN21. TROPICAL CYCLONE 16P (SIXTEEN), LOCATED APPROXIMATELY 497 NM NORTHWEST OF SUVA, FIJI, HAS TRACKED EASTWARD AT 16 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A VERY COMPACT SYSTEM CHARACTERIZED BY WELL DEFINED BANDING FEATURES TO THE NORTH AND SOUTH OF FLARING CONVECTION NEAR THE ASSESSED LOW LEVEL CIRCULATION CENTER (LLCC). A 302230Z GMI 89GHZ MICROWAVE IMAGE SHOWED WHAT APPEARED TO BE A LARGE MICROWAVE EYE-LIKE FEATURE WITH A CORE DEFINED BY LITTLE TO NO CONVECTION SURROUNDED BY DEEP CONVECTIVE BANDS, AND WHICH LENT HIGH CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 40 KNOTS WITH MODERATE CONFIDENCE AND IS HEDGED SLIGHTLY HIGHER THAN THE PGTW DVORAK CURRENT INTENSITY ESTIMATE OF T2.5 (35 KTS) BASED ON AND ADT ESTIMATE OF T2.7 (39 KTS), A SATCON ESTIMATE OF 40 KTS AND A 302117Z ASCAT-A SCATTEROMETER PASS WHICH INDICATED A FEW 40 KNOT WIND BARBS NEAR THE CENTER ON THE NORTHEAST SIDE. UPPER-LEVEL ANALYSIS REVEALS A MARGINALLY SUPPORTIVE ENVIRONMENT CHARACTERIZED BY LOW TO MODERATE (15-20 KTS) VWS, WEAK POLEWARD AND STRONG EQUATORWARD OUTFLOW, AND VERY WARM (30-31C) SSTS. THE SYSTEM IS CURRENTLY TRACKING EAST-SOUTHEAST ALONG THE SOUTHERN PERIPHERY OF THE NEAR EQUATORIAL RIDGE (NER) CENTERED TO THE NORTH. THE PRIMARY STEERING MECHANISM IS EXPECTED TO SLOWLY SHIFT FROM THE NER TO THE STR CENTERED TO THE EAST OVER THE NEXT 24 HOURS, LEADING TO A SOUTH- SOUTHEASTWARD TRACK AFTER TAU 24. AFTER CROSSING OVER THE EASTERN FIJIAN ISLANDS BY TAU 36, THE SYSTEM IS WILL BEGIN TO INTERACT WITH TC 15P, ULTIMATELY BECOMING ABSORBED BY TC 15P BETWEEN TAUS 48 AND 72. THE GENERAL ENVIRONMENT IS EXPECTED TO REMAIN FAVORABLE FOR ADDITIONAL DEVELOPMENT OVER THE NEXT 12-24 HOURS, WITH A PEAK OF 45 KTS EXPECTED BETWEEN TAU 12 AND TAU 24. INCREASING VWS AND CONVERGENT FLOW FROM THE OUTFLOW OF TC 15P WILL COMBINE TO SLOWLY WEAKEN THE SYSTEM BEGINNING AT TAU 36. TC 16P IS EXPECTED TO DISSIPATE AS A DISTINCT TROPICAL CYCLONE AS IT MERGES WTIH TC 15P NO LATER THAN TAU 72. NUMERICAL MODEL GUIDANCE IS IN GOOD CROSS-TRACK AGREEMENT THROUGH THE FORECAST PERIOD BUT DISPLAYS RELATIVELY HIGH ALONG-TRACK UNCERTAINTY AS MODELS ARE STRUGGLING SOMEWHAT WITH THE BINARY INTERACTION AND MERGER OF THE TWO SYSTEMS. THE JTWC FORECAST REMAINS CONSISTENT WITH THE PREVIOUS FORECAST TRACK, AND LIES JUST TO THE EAST AND SLIGHTLY FASTER THAN THE MULTI-MODEL CONSENSUS. IN LIGHT OF THE HIGHLY UNCERTAIN NATURE OF THE BINARY INTERACTION, THERE IS LOW CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 310000Z IS 15 FEET. NEXT WARNINGS AT 310900Z, 311500Z, 312100Z AND 010300Z. REFER TO TROPICAL CYCLONE 15P (ANA) WARNINGS (WTPS31 PGTW) FOR SIX-HOURLY UPDATES. REFER TO TROPICAL CYCLONE 17P (SEVENTEEN) WARNINGS (WTPS33 PGTW) FOR SIX-HOURLY UPDATES. // NNNN