WTPS33 PGTW 310300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 17P (SEVENTEEN) WARNING NR 001// RMKS/ 1. TROPICAL CYCLONE 17P (SEVENTEEN) WARNING NR 001 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 13.9S 152.3E MOVEMENT PAST SIX HOURS - 090 DEGREES AT 08 KTS POSITION ACCURATE TO WITHIN 040 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 - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT REPEAT POSIT: 13.9S 152.3E --- FORECASTS: 12 HRS, VALID AT: 311200Z --- 13.8S 154.8E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 100 DEG/ 15 KTS --- 24 HRS, VALID AT: 010000Z --- 14.3S 157.9E 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 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 110 DEG/ 17 KTS --- 36 HRS, VALID AT: 011200Z --- 15.4S 161.2E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 165 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 120 DEG/ 16 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 020000Z --- 16.9S 164.2E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 12 KTS --- 72 HRS, VALID AT: 030000Z --- 20.5S 167.4E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 165 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 040000Z --- 22.7S 168.0E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 215 DEG/ 05 KTS --- 120 HRS, VALID AT: 050000Z --- 24.3S 166.8E 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 13.9S 152.9E. 31JAN21. TROPICAL CYCLONE (TC) 17P (SEVENTEEN), LOCATED APPROXIMATELY 417 NM EAST-NORTHEAST OF CAIRNS, AUSTRALIA, HAS TRACKED EASTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTI-SPECTRAL SATELLITE IMAGERY DEPICTS A COMPACT AREA OF DEEP CONVECTION WITH LOW LEVEL BANDING WRAPPING IN FROM THE SOUTHEAST. A 310005Z 37GHZ GMI MICROWAVE IMAGE DEPICTS A DISTINCT MICROWAVE EYE, GIVING OVERALL GOOD CONFIDENCE IN THE INTIAL POSITION OF TC 17P. THE CURRENT INTENSITY IS SET AT 40KTS, HEDGED BETWEEN CURRENT DVORAK INTENSITY ESTIMATES OF T2.5 FROM PGTW AND T3.0 FROM KNES. A PARTIAL 312230Z METOP-C ASCAT PASS SHOWS A PASS OF 30KT BARBS TO THE NORTHEAST OF THE LOW LEVEL CIRCULATION CENTER. ENVIRONMENTAL ANALYSIS REVEALS THAT THE SYSTEM LIES IN AN OVERALL SUPPORTIVE REGION CHARACTERIZED BY WARM (30-31C) SEA SURFACE TEMPERATURES, LOW (10-15 KT) VERTICAL WIND SHEAR WITH ROBUST POLEWARD OUTFLOW. TC 17P IS CURRENTLY TRACKING TOWARDS THE EAST UNDER THE STEERING INFLUENCE OF A NEAR EQUATORIAL RIDGE (NER) CENTERED TO THE NORTH. THE PRIMARY STEERING MECHANISM WILL SHIFT AS A SUBTROPICAL RIDGE (STR) GRADUALLY BUILDS IN FROM THE EAST, DRIVING TC 17P SOUTHEASTWARD. OVER THE NEXT 24 TO 48 HOURS, THE SYSTEM IS FORECAST TO INTENSIFY DUE TO A STRONG POLEWARD OUTFLOW CHANNEL AND WARM SEA SURFACE TEMPERATURES. HOWEVER, AFTER TAU 48, SHEAR IS EXPECTED TO INCREASE TO OVER 25KTS AS A TROUGH PASSES ALONG ITS SOUTHERN PERIPHERY. THE INCREASED SHEAR WILL GRADUALLY DISSIPATE TC 17P DOWN TO 30 KNOTS AS IT ROUNDS NEW CALEDONIA. NUMERICAL TRACK MODEL GUIDANCE IS IN OVERALL FAIR AGREEMENT THROUGH TAU 96 WITH A CROSS TRACK SPREAD OF APPROXIMATELY 300NM. THE JTWC FORECAST TRACK LIES NEAR CONSENSUS. DUE TO THE UNCERTAIN NATURE OF THE PASSING TROUGH, DISSIPATION TIMING IS UNCERTAIN. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 310000Z IS 12 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 16P (SIXTEEN) WARNINGS (WTPS32 PGTW) FOR SIX-HOURLY UPDATES.// NNNN