WTPS31 PGTW 040300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 23P (NIRAN) WARNING NR 013// RMKS/ 1. TROPICAL CYCLONE 23P (NIRAN) WARNING NR 013 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 040000Z --- NEAR 15.2S 148.7E MOVEMENT PAST SIX HOURS - 090 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 020 NM POSITION BASED ON EYE FIXED BY A COMBINATION OF SATELLITE, RADAR AND SYNOPTIC DATA PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 105 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 165 NM NORTHWEST QUADRANT REPEAT POSIT: 15.2S 148.7E --- FORECASTS: 12 HRS, VALID AT: 041200Z --- 15.9S 150.6E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 210 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 200 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 115 DEG/ 16 KTS --- 24 HRS, VALID AT: 050000Z --- 17.3S 153.5E MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 230 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 210 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 120 DEG/ 20 KTS --- 36 HRS, VALID AT: 051200Z --- 19.3S 157.2E MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 260 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 210 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 120 DEG/ 25 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 060000Z --- 21.7S 161.8E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 260 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 190 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 115 DEG/ 26 KTS --- 72 HRS, VALID AT: 070000Z --- 25.9S 172.2E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING SUBTROPICAL RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 210 NM NORTHEAST QUADRANT 160 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 170 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 110 DEG/ 26 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 080000Z --- 29.0S 176.7W MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY SUBTROPICAL RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 170 NM NORTHWEST QUADRANT --- REMARKS: 040300Z POSITION NEAR 15.4S 149.2E. 04MAR21. TROPICAL CYCLONE (TC) 23P (NIRAN), LOCATED APPROXIMATELY 196 NM EAST-NORTHEAST OF CAIRNS, AUSTRALIA, HAS TRACKED EASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A FORMATIVE 20-NM EYE WITHIN A SYMMETRIC CENTRAL DENSE OVERCAST WITH A BANDING FEATURE OVER THE NORTHERN SEMICIRCLE. MSI SUPPORTS THE INITIAL POSITION AND THE RECENT EASTWARD TRACK MOTION WITH GOOD CONFIDENCE. ANIMATED RADAR IMAGERY FROM THE WILLIS ISLAND RADAR REVEALS SPIRAL BANDING WRAPPING INTO A WELL DEFINED EYEWALL WITH A SMALL BREAK IN THE SOUTH QUADRANT. THE INITIAL INTENSITY IS ASSESSED AT 85 KNOTS BASED ON DVORAK ESTIMATES RANGING FROM T4.5 (77 KNOTS) TO T5.0 (90 KNOTS). TC 23P IS LOCATED ABOUT 98NM NORTHWEST OF WILLIS ISLAND (16.29S 149.97E), WHICH IS REPORTING 10-MINUTE SUSTAINED WINDS OF 25-30 KTS GUSTING TO 37 KTS. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH GOOD OUTFLOW, LOW VERTICAL WIND SHEAR (VWS) AND WARM SST VALUES (29-30C). TC 23P IS FORECAST TO ACCELERATE EAST-SOUTHEASTWARD THROUGH THE FORECAST PERIOD WITHIN THE ENHANCED FLOW BETWEEN A STRONG MAJOR TROUGH TO THE SOUTH AND THE STEERING RIDGE ENTRENCHED TO THE NORTH AND NORTHEAST. NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A 260NM SPREAD IN SOLUTIONS AT TAU 72 LENDING MODERATE CONFIDENCE TO THE JTWC FORECAST TRACK. BASED ON THE TRIGGERING OF RAPID INTENSIFICATION PREDICTION AIDS, THE PRESENCE OF A COMPACT CYAN RING FEATURE IN THE 032031Z SSMIS 37GHZ COLOR COMPOSITE IMAGE, WHICH IS TYPICALLY INDICATIVE OF IMMINENT RAPID INTENSIFICATION, AND THE FORMATION OF A SMALL EYE IN EIR, TC 23P IS EXPECTED TO RAPIDLY INTENSIFY TO A PEAK OF 120 KNOTS BY TAU 24 BUT THIS COULD OCCUR EARLIER AND PEAK AT A HIGHER INTENSITY. AFTER TAU 36, TC 23P WILL ENCOUNTER INCREASING VWS ASSOCIATED WITH THE SUBTROPICAL WESTERLIES AND WILL WEAKEN STEADILY THROUGH THE REMAINDER OF THE PERIOD. NEAR TAU 72, THE SYSTEM WILL COMMENCE SUBTROPICAL TRANSITION AS IT BECOMES EMBEDDED WITHIN THE SUBTROPICAL WESTERLIES AND INTERACTS WITH WEAK BAROCLINICITY ALONG THE NORTHERN EDGE OF THE BAROCLINIC ZONE. THE SYSTEM SHOULD COMPLETE SUBTROPICAL TRANSITION AS A STORM- FORCE LOW BY TAU 96. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 040000Z IS 30 FEET. NEXT WARNINGS AT 040900Z, 041500Z, 042100Z AND 050300Z.// NNNN