WTPS31 PGTW 050300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 23P (NIRAN) WARNING NR 017// RMKS/ 1. TROPICAL CYCLONE 23P (NIRAN) WARNING NR 017 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 050000Z --- NEAR 16.7S 154.6E MOVEMENT PAST SIX HOURS - 110 DEGREES AT 22 KTS POSITION ACCURATE TO WITHIN 015 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 060 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 155 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 135 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 215 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 305 NM NORTHWEST QUADRANT REPEAT POSIT: 16.7S 154.6E --- FORECASTS: 12 HRS, VALID AT: 051200Z --- 18.7S 158.7E MAX SUSTAINED WINDS - 125 KT, GUSTS 150 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 240 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 210 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 115 DEG/ 23 KTS --- 24 HRS, VALID AT: 060000Z --- 20.7S 163.0E MAX SUSTAINED WINDS - 110 KT, GUSTS 135 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 - 080 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 220 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 160 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 120 DEG/ 25 KTS --- 36 HRS, VALID AT: 061200Z --- 23.2S 167.6E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 115 DEG/ 26 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 070000Z --- 25.5S 172.8E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 115 DEG/ 25 KTS --- 72 HRS, VALID AT: 080000Z --- 29.2S 176.6W MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT --- REMARKS: 050300Z POSITION NEAR 17.2S 155.6E. 05MAR21. TROPICAL CYCLONE (TC) 23P (NIRAN), LOCATED APPROXIMATELY 506 NM EAST OF CAIRNS, AUSTRALIA, HAS TRACKED EAST-SOUTHEASTWARD AT 22 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY SHOWS A TIGHT EYE (10NM) FEATURE. THE CURRENT INTENSITY OF 110 KNOTS IS HEDGED SLIGHTLY BELOW MULTI-AGENCY DVORAK INTENSITY FIXES OF T5.5-6.0 (102 KNOTS TO 115 KNOTS). TC 23P IS CURRENTLY IN A FAVORABLE ENVIRONMENT FOR CONTINUED INTENSIFICATION WITH LOW VERITCAL WIND SHEAR (5-10 KNOTS), WARM SEA SURFACE TEMPERATURES (29 DEGREES CELSIUS) AND STRONG POLEWARD OUTFLOW. TC 23P IS CURRENTLY MOVING ALONG AN EXTENSION OF THE SUBTROPICAL RIDGE POSITIONED TO THE NORTHEAST AND WILL CONTINUE ALONG THIS FEATURE FOR THE REMAINDER OF THE FORECAST. WHILE TC 23P MAINTAINS ITS FAVORABLE ENIVONRMENT, IT IS EXPECTED TO INTENSIFY UP TO 125 KNOTS BY TAU 12 BEFORE FALLING STEEPLY TO 75 KNOTS AT TAU 36 AS TC 23P ENCOUNTERS HIGH VERTICAL WIND SHEAR (25-30 KNOTS) AND DECREASED UPPER LEVEL SUPPORT ALONG ITS TRACK SOUTHEASTWARD. TC 23P IS FORECAST TO BEGIN SUBTROPICAL TRANSITION BY TAU 36 AND COMPLETE TRANSITION TO A STORM FORCE SUBTROPICAL LOW BY TAU 72. NUMERICAL TRACK MODEL GUIDANCE IS IN VERY TIGHT AGREEMENT THROUGH TAU 24, INCREASING TO AN ALONG TRACK SPREAD OF 600NM BY TAU 72. THE JTWC FORECAST TRACK LIES SLIGHTLY NORTH OF CONSENSUS MEAN TRACK AFTER TAU 48. WHILE THERE IS HIGH CONFIDENCE IN THE FIRST PORTION OF THE FORECAST, THERE IS LOW CONFIDENCE IN THE EXTENDED JTWC FORECAST TRACK. THERE IS LOW CONFIDENCE IN THE JTWC INTENSITY FORECAST GIVEN THE COMPACT NATURE OF THE SYSTEM. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 050000Z IS 35 FEET. NEXT WARNINGS AT 050900Z, 051500Z, 052100Z AND 060300Z.// NNNN