WTPS31 PGTW 020300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 23P (NIRAN) WARNING NR 005// RMKS/ 1. TROPICAL CYCLONE 23P (NIRAN) WARNING NR 005 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 020000Z --- NEAR 15.1S 147.7E MOVEMENT PAST SIX HOURS - 045 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 035 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 - 050 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT REPEAT POSIT: 15.1S 147.7E --- FORECASTS: 12 HRS, VALID AT: 021200Z --- 15.0S 147.9E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 065 DEG/ 01 KTS --- 24 HRS, VALID AT: 030000Z --- 14.9S 148.1E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 100 DEG/ 02 KTS --- 36 HRS, VALID AT: 031200Z --- 15.0S 148.6E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 120 DEG/ 04 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 040000Z --- 15.4S 149.3E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 110 DEG/ 09 KTS --- 72 HRS, VALID AT: 050000Z --- 16.7S 153.0E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 170 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 115 DEG/ 15 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 060000Z --- 19.1S 158.8E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 170 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 125 DEG/ 21 KTS --- 120 HRS, VALID AT: 070000Z --- 24.0S 166.4E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT 180 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 160 NM NORTHWEST QUADRANT --- REMARKS: 020300Z POSITION NEAR 15.1S 147.7E. 02MAR21. TROPICAL CYCLONE 23P (NIRAN), LOCATED APPROXIMATELY 154 NM NORTHEAST OF CAIRNS, AUSTRALIA, HAS TRACKED NORTHEASTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE (MSI) IMAGERY INDICATES STRONG FLARING CONVECTION CONSOLIDATING NEAR THE LOW LEVEL CIRCULATION (LLC). THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE USING A BULLSEYE PASS FROM A 012353Z METOP-B ASCAT. THE SYSTEM CONTINUES TO INDICATE A SLIGHT TILT TO THE WEST BETWEEN THE SURFACE AND THE UPPER LEVELS USING THE TWO MICROWAVE IMAGES FROM 012100Z SSMIS 37GHZ AND 91GHZ WHICH IS INDICATIVE OF THE INCREASE IN VERTICAL WIND SHEAR. STRONG SOUTHERLY WIND OBSERVATIONS FROM BOUGAINVILLE REEF INDICATE THE SYSTEM IS WELL TO THE EAST- NORTHEAST AND VALIDATE THE INITIAL INTENSITY OF 45 KNOTS AND THE AFOREMENTIONED ASCAT IMAGE. INITIAL INTENSITY IS HEDGED SLIGHTLY HIGHER THAN AGENCY DVORAK INTENSITY ESTIMATES FROM PGTW OF T2.5 (35 KTS), AND MORE IN LINE WITH KNES/ABRF AND ADVANCED DVORAK TECHNIQUE (ADT) T3.0 (45KTS), AND THE AFOREMENTIONED ASCAT IMAGE. THE OVERALL ENVIRONMENT IS INCREASINGLY FAVORABLE; VERTICAL WIND SHEAR (VWS) IS LOW TO MODERATE (10-15 KTS) FROM THE EAST, SSTS ARE VERY WARM (29- 30C) AND THE OUTFLOW PATTERN IS BEGINNING TO SHOW A MORE DEFINED RADIAL OUTFLOW. THE STEERING PATTERN REMAINS COMPLEX, WITH THE SYSTEM REMAINING TRAPPED BETWEEN A NEAR-EQUATORIAL RIDGE (NER) TO THE NORTHEAST AND A SUBTROPICAL RIDGE (STR) OVER CENTRAL AUSTRALIA. THIS PATTERN IS EXPECTED TO REMAIN FOR THE NEXT 24 TO 36 HOURS AS THE STR TO THE WEST IS EXPECTED TO WEAKEN AND MOVE SOUTHWEST WHILE THE NER STRENGTHENS AND MOVES SOUTHWEST, INCREASING THE GRADIENT TO THE NORTHEAST OF THE SYSTEM, ALLOWING IT TO MOVE SOUTHEASTWARD AFTER A SLOW QUASI-STATIONARY TRACK. ONCE ESTABLISHED ON THE SOUTHEASTWARD TRACK, THE SYSTEM WILL ACCELERATE AHEAD OF AN APPROACHING MAJOR SHORTWAVE TROUGH. THE SYSTEM STARTS TO MOVE CLOSER TO THE SHORTWAVE TROUGH DURING TAU 48, AND THE OUTFLOW IMPROVES BY TAPPING INTO THE DEEP WESTERLIES. THE OUTFLOW WILL ALLOW FOR A FASTER RATE OF INTENSIFICATION REACHING A PEAK OF 70 KTS BETWEEN TAU 72 AND 96. AVAILABLE MODEL GUIDANCE SHOWS A HIGH DEGREE OF UNCERTAINTY AS WOULD BE EXPECTED FOR A SYSTEM IN A WEAK STEERING ENVIRONMENT AND WILL MOST LIKELY FAVOR A QUASI-STATIONARY MOTION AND DRIFT SLOWLY TO THE EAST-NORTHEAST BEFORE TURNING TO THE SOUTHEAST. THE ALONG-TRACK SPREAD REMAINS LARGE AT 600NM BETWEEN MULTI-MODEL CONSENSUS WITH GFS AND ECMWF. THE JTWC FORECAST TRACK LIES JUST EQUATORWARD OF THE MULTI-MODEL CONSENSUS AND DUE TO THE LARGE ALONG-TRACK SPREAD IN LATER TAUS, THERE IS OVERALL LOW CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 020000Z IS 18 FEET. NEXT WARNINGS AT 020900Z, 021500Z, 022100Z, AND 030300Z.// NNNN