WTPS31 PGTW 300900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 15P (ANA) WARNING NR 002// RMKS/ 1. TROPICAL CYCLONE 15P (ANA) WARNING NR 002 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 300600Z --- NEAR 16.6S 177.0E MOVEMENT PAST SIX HOURS - 135 DEGREES AT 07 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 210 NM NORTHWEST QUADRANT REPEAT POSIT: 16.6S 177.0E --- FORECASTS: 12 HRS, VALID AT: 301800Z --- 17.5S 177.8E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 150 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 165 DEG/ 05 KTS --- 24 HRS, VALID AT: 310600Z --- 18.5S 178.1E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 220 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 175 DEG/ 08 KTS --- 36 HRS, VALID AT: 311800Z --- 20.1S 178.2E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 260 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 165 DEG/ 08 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 010600Z --- 21.7S 178.6E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 250 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 150 DEG/ 07 KTS --- 72 HRS, VALID AT: 020600Z --- 24.3S 179.8W MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 140 DEG/ 10 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 030600Z --- 27.2S 177.0W 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 - 120 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 140 DEG/ 11 KTS --- 120 HRS, VALID AT: 040600Z --- 30.3S 173.7W MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 300900Z POSITION NEAR 16.8S 177.2E. 30JAN21. TROPICAL CYCLONE (TC) 15P (ANA), LOCATED APPROXIMATELY 121 NM NORTHWEST OF SUVA, FIJI, HAS TRACKED SOUTHEASTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A COMPACT, CONSOLIDATING CORE WITH SPIRAL BANDING OVER THE EASTERN SEMICIRCLE. A 300515Z SSMIS 91GHZ COMPOSITE MICROWAVE IMAGE REVEALS DEEP CONVECTIVE BANDING WRAPPING INTO A WEAK, DEVELOPING MICROWAVE EYE FEATURE WITH LIMITED DEEP CONVECTION OVER THE WESTERN SEMICIRCLE. OVERALL, THERE IS GOOD CONFIDENCE IN THE INITIAL POSITION. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH LOW VERTICAL WIND SHEAR (VWS) AND ROBUST EQUATORWARD OUTFLOW. ADDITIONALLY, SST VALUES (29-30C) REMAIN CONDUCIVE. HOWEVER, POLEWARD OUTFLOW IS WEAK DUE TO CONVERGENT FLOW OVER THE SOUTHWEST QUADRANT AND THE LACK OF A SIGNIFICANT UPPER- LEVEL TROUGH, WHICH HAS PROPAGATED EASTWARD. TC 15P IS FORECAST TO REACH A PEAK INTENSITY OF 55 KNOTS WITHIN THE NEXT 36 HOURS AS IT TURNS SOUTHWARD ALONG THE WESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) EXTENSION TO THE EAST, HOWEVER, INTERACTION WITH LAND SHOULD LIMIT DEVELOPMENT. AFTER TAU 36, TC 15P IS EXPECTED TO ACCELERATE SOUTH-SOUTHEASTWARD TO SOUTHEASTWARD ALONG THE SOUTHWESTERN PERIPHERY OF THE STR. THROUGH TAU 72, TC 15P SHOULD GRADUALLY WEAKEN AS IT ENCOUNTERS INCREASING VWS (30-35 KNOTS) ASSOCIATED WITH THE SUBTROPICAL WESTERLIES AS WELL AS SLIGHTLY COOLER SST (26-27C). IN THE EXTENDED PERIOD, THE SYSTEM WILL WEAKEN MORE RAPIDLY DUE TO COOL SST (26-23C) AND SHOULD DISSIPATE BY TAU 120. NUMERICAL MODEL GUIDANCE REMAINS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK WITH A 170NM SPREAD IN MODEL SOLUTIONS AT TAU 96 AND TAU 120. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 300600Z IS 14 FEET. NEXT WARNINGS AT 301500Z, 302100Z, 310300Z AND 310900Z.// NNNN