WTPS32 PGTW 030300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 17P (IRIS) WARNING NR 016 02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 030000Z --- NEAR 17.0S 149.0E MOVEMENT PAST SIX HOURS - 090 DEGREES AT 01 KTS POSITION ACCURATE TO WITHIN 045 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 - 085 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT REPEAT POSIT: 17.0S 149.0E --- FORECASTS: 12 HRS, VALID AT: 031200Z --- 17.5S 149.5E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 005 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 135 DEG/ 05 KTS --- 24 HRS, VALID AT: 040000Z --- 18.2S 150.2E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 190 NM SOUTHEAST QUADRANT 150 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 130 DEG/ 04 KTS --- 36 HRS, VALID AT: 041200Z --- 18.7S 150.8E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 170 NM SOUTHEAST QUADRANT 145 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 130 DEG/ 02 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 050000Z --- 19.0S 151.2E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 135 DEG/ 01 KTS --- 72 HRS, VALID AT: 060000Z --- 19.3S 151.5E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 010 NM NORTHEAST QUADRANT 135 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 180 DEG/ 01 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 070000Z --- 19.7S 151.5E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 000 NM NORTHEAST QUADRANT 135 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 270 DEG/ 01 KTS --- 120 HRS, VALID AT: 080000Z --- 19.7S 151.0E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 030300Z POSITION NEAR 17.1S 149.1E. TROPICAL CYCLONE 17P (IRIS), LOCATED APPROXIMATELY 184 NM EAST OF CAIRNS, AUSTRALIA, HAS TRACKED EASTWARD AT 01 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED MULTI-SPECTRAL (MSI) SATELLITE SHOWS A DEEP CONVECTION TO THE SOUTH OF A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE MSI LOOP AND WILLIS ISLAND RADAR LOOP. THE INITIAL INTENSITY OF 45 KNOTS IS BASED ON MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T3.0 (45 KNOTS) AND SUPPORTED BY A SATCON ESTIMATE OF 47 KNOTS. UPPER LEVEL ANALYSIS REVEALS THE SYSTEM HAS AN EXCELLENT POLEWARD OUTFLOW CHANNEL DUE TO AN UPPER LEVEL ANTICYCLONE CENTERED TO THE NORTHEAST. ENVIRONMENTAL ANALYSIS SHOWS THE SYSTEM IS IN AN AREA OF LOW (5-10 KNOTS) VERTICAL WIND SHEAR, AND IS TRACKING THROUGH WARM (28 CELSIUS) SEA SURFACE TEMPERATURES. OVERALL FAVORABLE CONDITIONS WILL ALLOW FOR STEADY INTENSIFICATION THROUGH TAU 36, REACHING A PEAK INTENSITY OF 65 KNOTS. TC 17P IS UNDER COMPETING STEERING INFLUENCES WITH A NEAR- EQUATORIAL RIDGE (NER) LOCATED TO THE NORTHEAST AND A SUBTROPICAL RIDGE (STR) ANCHORED OVER AUSTRALIA. TC IRIS IS FORECAST TO TRACK SOUTHEAST THROUGH TAU 48 ALONG THE NER. AROUND THIS TIME, THE STR WILL TRANSIT TO THE WEST AND A TROUGH MOVES IN OVER CENTRAL AUSTRALIA. AFTER TAU 48 THE SYSTEM WILL BECOME QUASI STATIONARY IN AN AREA OF INCREASINGLY UNFAVORABLE VERTICAL WIND SHEAR, THE RESULT OF THE TROUGH OVER AUSTRALIA. THE SYSTEM WILL STEADILY DISSIPATE BETWEEN TAU 72 AND TAU 120, WITH THE REMNANT SURFACE LOW LEVEL TRACKING BACK TO THE NORTHWEST DUE TO THE SOUTHEASTERLY SURFACE FLOW. HOWEVER, THERE IS A BIFURCATION IN THE AVAILABLE MODEL GUIDANCE. AN ALTERNATE SCENARIO, AND THE PREVIOUS FORECAST PHILOSOPHY, IS THAT THE SYSTEM COULD TRACK EASTWARD AROUND THE SOUTHERN EXTENT OF THE NER AND DISSIPATE UNDER INCREASING VWS. DUE TO THE BIFURCATION IN THE DYNAMIC MODEL GUIDANCE, THERE IS OVERALL LOW CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 030000Z IS 12 FEET. NEXT WARNINGS AT 030900Z, 031500Z, 032100Z AND 040300Z. REFER TO TROPICAL CYCLONE 18P (JOSIE) WARNINGS (WTPS31 PGTW) FOR SIX-HOURLY UPDATES.//