WTXS32 PGTW 232100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING NR// RMKS/ 1. TROPICAL CYCLONE 15S (MARCUS) WARNING NR 032 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 231200Z --- NEAR 22.3S 106.0E MOVEMENT PAST SIX HOURS - 170 DEGREES AT 11 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 185 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT REPEAT POSIT: 22.3S 106.0E --- FORECASTS: 12 HRS, VALID AT: 240000Z --- 25.0S 106.7E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 185 NM SOUTHEAST QUADRANT 160 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 170 DEG/ 11 KTS --- 24 HRS, VALID AT: 241200Z --- 27.1S 107.1E 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 - 065 NM NORTHEAST QUADRANT 175 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 165 DEG/ 10 KTS --- 36 HRS, VALID AT: 250000Z --- 29.0S 107.7E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 231500Z POSITION NEAR 23.0S 106.2E. TROPICAL CYCLONE (TC) 15S (MARCUS), LOCATED APPROXIMATELY 423 NM WEST-SOUTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTH- SOUTHEASTWARD AT 15 KNOTS OVER THE PAST SIX HOURS. ENHANCED INFRARED IMAGERY SHOWS WHAT APPEARS TO BE AN EYE FEATURE, BUT A 231445Z AMSU- B 89 GHZ MICROWAVE IMAGE INDICATES THAT THE LLCC HAS BEGUN TO SEPARATE FROM THE UPPER LEVEL CONVECTIVE SIGNATURE, LEADING TO PLACEMENT OF THE INITIAL POSITION FURTHER TO THE NORTHWEST THAN WHAT THE IR IMAGERY WOULD SUGGEST. THE INITIAL INTENSITY OF 60 KNOTS IS CONSISTENT WITH A CONSENSUS OF SUBJECTIVE DVORAK CURRENT INTENSITY ESTIMATES OF T4.0 (65 KNOTS) FROM BOTH PGTW AND KNES, AND AUTOMATED INTENSITY ESTIMATES FROM CIMSS OF T3.9 (59 KNOTS). TC 15S IS RAPIDLY WEAKENING AS IT TRACKS POLEWARD ALONG THE PERIPHERY OF A DEEP SUBTROPICAL STEERING RIDGE SITUATED OVER WESTERN AUSTRALIA. THE SYSTEM IS EXPECTED TO CONTINUE MOVING ALONG THE RIDGE PERIPHERY AND WEAKEN AS IT PASSES OVER PROGRESSIVELY COOLER WATER AND INTO AN AREA OF INCREASING VERTICAL WIND SHEAR. THE RAPID WEAKENING TREND IS FORECAST TO CONTINUE THROUGH THE FORECAST PERIOD, LEADING TO DISSIPATION BY TAU 36. FORECAST MODEL GUIDANCE IS IN STRONG AGREEMENT, LENDING HIGH CONFIDENCE TO THE CURRENT JTWC FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 231200Z IS 28 FEET. NEXT WARNINGS AT 232100Z, 240300Z, 240900Z AND 241500Z.//