WTXS32 PGTW 080900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 15S (ERNIE) WARNING NR 005// RMKS/ 1. TROPICAL CYCLONE 15S (ERNIE) WARNING NR 005 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 080600Z --- NEAR 16.6S 110.0E MOVEMENT PAST SIX HOURS - 215 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 020 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 065 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT REPEAT POSIT: 16.6S 110.0E --- FORECASTS: 12 HRS, VALID AT: 081800Z --- 16.9S 108.8E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 005 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 250 DEG/ 07 KTS --- 24 HRS, VALID AT: 090600Z --- 17.4S 107.5E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 015 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 250 DEG/ 10 KTS --- 36 HRS, VALID AT: 091800Z --- 18.0S 105.5E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 005 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 025 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 055 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 250 DEG/ 12 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 100600Z --- 18.8S 103.2E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 010 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 005 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 245 DEG/ 10 KTS --- 72 HRS, VALID AT: 110600Z --- 20.5S 99.2E MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 080900Z POSITION NEAR 16.7S 109.7E. TROPICAL CYCLONE (TC) 15S (ERNIE), LOCATED APPROXIMATELY 413 NM NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A 080144Z AMSU 89 GHZ IMAGE CONTINUE TO DEPICT TIGHTLY CURVED, DEEP CONVECTIVE BANDING WRAPPING INTO A DEFINED CIRCULATION, AND SUPPORT THE CURRENT JTWC BEST TRACK POSITION WITH HIGH CONFIDENCE. HOWEVER, THE SYSTEM HAS LOST ITS EYE FEATURE AND CLOUD- TOPS HAVE WARMED CONSIDERABLY OVER THE PAST 6-HOURS, INDICATING THAT A RAPID WEAKENING TREND HAS COMMENCED. THE INITIAL INTENSITY OF 95 KNOTS IS SLIGHTLY BELOW AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T6.0 (115 KNOTS), AND IS SUPPORTED BY AMSU AND SSMIS OBJECTIVE INTENSITY ESTIMATES BETWEEN 90 TO 95 KNOTS. ENVIRONMENTAL CONDITIONS NO LONGER SUPPORT DEVELOPMENT DUE TO INCREASED (15 TO 20 KNOTS) VERTICAL WIND SHEAR AND UPPER-LEVEL CONVERGENCE OVER THE NORTHERN PERIPHERY OF THE SYSTEM, DESPITE FAVORABLE SSTS AND A GOOD POLEWARD OUTFLOW CHANNEL. TC ERNIE IS CURRENTLY TRACKING SOUTHWESTWARD ALONG THE WESTERN PERIPHERY OF A DEEP-LAYERED STR POSITIONED OVER NORTHWEST AUSTRALIA. THIS STEERING FEATURE WILL PREVAIL THROUGH THE DURATION OF THE FORECAST PERIOD MAINTAINING THE SYSTEM ON A PREDOMINANTLY SOUTHWESTWARD COURSE. BASED ON THIS TRACK, TC 15S IS FORECAST TO ENTER AN UNFAVORABLE SHEAR ENVIRONMENT WITH DECREASING UPPER-LEVEL OUTFLOW, RESULTING IN RAPID WEAKENING OF THE SYSTEM OVER THE NEXT 48 HOURS, AND FULL DISSIPATION BY TAU 72. DYNAMIC MODEL GUIDANCE REMAIN IN OVERALL GOOD AGREEMENT ON THE UPPER-LEVEL STEERING PATTERN LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 080600Z IS 25 FEET. NEXT WARNINGS AT 082100Z AND 090900Z.//