WTPS32 PGTW 030900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 17P (IRIS) WARNING NR 017 02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 030600Z --- NEAR 17.8S 149.7E MOVEMENT PAST SIX HOURS - 140 DEGREES AT 10 KTS POSITION ACCURATE TO WITHIN 015 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 - 115 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 17.8S 149.7E --- FORECASTS: 12 HRS, VALID AT: 031800Z --- 18.5S 150.4E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 185 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 130 DEG/ 05 KTS --- 24 HRS, VALID AT: 040600Z --- 19.1S 151.2E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 165 NM SOUTHEAST QUADRANT 135 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 125 DEG/ 03 KTS --- 36 HRS, VALID AT: 041800Z --- 19.4S 151.7E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 005 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 150 DEG/ 02 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 050600Z --- 19.7S 151.9E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 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 - 025 NM NORTHEAST QUADRANT 165 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 180 DEG/ 00 KTS --- 72 HRS, VALID AT: 060600Z --- 19.9S 151.9E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 025 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 205 DEG/ 01 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 070600Z --- 20.1S 151.8E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER VECTOR TO 120 HR POSIT: 270 DEG/ 01 KTS --- 120 HRS, VALID AT: 080600Z --- 20.1S 151.5E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 030900Z POSITION NEAR 18.0S 149.9E. TROPICAL CYCLONE 17P (IRIS), LOCATED APPROXIMATELY 230 NM EAST- SOUTHEAST OF CAIRNS, AUSTRALIA, HAS TRACKED SOUTHEASTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED MSI SHOWS THE SYSTEM APPEARS TO HAVE DISLODGED FROM A QUASI-STATIONARY (QS) STATE. HOWEVER, THE CENTRAL CONVECTION REMAINS DISPLACED SOUTHEAST OF THE LLC. THE INITIAL POSITION IS EXTRAPOLATED WITH GOOD CONFIDENCE FROM LOW CLOUD BANDS FEEDING INTO THE LLC THAT IS APPARENT IN THE MSI LOOP. THIS POSITION IS ALSO LINED UP WITH AN ELONGATED LOW REFLECTIVITY CIRCULATION FEATURE IN THE 030451Z SSMI MICROWAVE PASS. THE INITIAL INTENSITY IS BASED ON CONGRUENT DVORAK ESTIMATES FROM PGTW AND KNES OF T3.0 (45 KNOTS). UPPER LEVEL ANALYSIS INDICATES TC 17P IS IN AN AREA OF MODERATE (15-20 KNOT) NORTHWESTERLY VWS. HOWEVER, AN EXCELLENT POLEWARD OUTFLOW CHANNEL IS PARTIALLY OFFSETTING THE VWS AND PROVIDING VENTILATION TO THE CONVECTION. ALONG-TRACK SSTS AT 29C ARE ALSO CONDUCIVE. TC IRIS IS NOW TRACKING ALONG THE SOUTHWEST PERIPHERY OF THE NER TO THE NORTHEAST AS THE COMPETING STR TO THE SOUTHWEST HAS RECEDED WESTWARD. THE CYCLONE WILL CONTINUE ON THIS TRACK UP TO TAU 36; AFTERWARD, THE STR WILL RE-BUILD AND ONCE AGAIN COMPETE FOR STEERING, TRIGGERING ANOTHER QS STATE. BY TAU 96, THE STR WILL EXTEND TO THE SOUTH AND ASSUME STEERING, NUDGING THE CYCLONE SLOWLY WESTWARD. THE AFOREMENTIONED MARGINALLY FAVORABLE CONDITIONS WILL PREVAIL FOR ABOUT TWO DAYS AND PROMOTE MODERATE INTENSIFICATION UP TO 60 KNOTS. AFTERWARD, INCREASING VWS WILL MOSTLY BE RESPONSIBLE FOR A GRADUAL WEAKENING TOWARD DISSIPATION BY END OF FORECAST. THE AVAILABLE NUMERIC GUIDANCE IS SIGNIFICANTLY SPREAD AND BIFURCATED. IN VIEW OF THIS, THERE IS OVERALL LOW CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 030600Z IS 14 FEET. NEXT WARNINGS AT 031500Z, 032100Z, 040300Z AND 040900Z.//