WTXS31 PGTW 272100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 03S (THREE) WARNING NR 003 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 271800Z --- NEAR 19.5S 116.4E MOVEMENT PAST SIX HOURS - 235 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 030 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 - 070 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT REPEAT POSIT: 19.5S 116.4E --- FORECASTS: 12 HRS, VALID AT: 280600Z --- 20.3S 114.0E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 260 DEG/ 09 KTS --- 24 HRS, VALID AT: 281800Z --- 20.6S 112.1E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 260 DEG/ 08 KTS --- 36 HRS, VALID AT: 290600Z --- 20.8S 110.5E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 255 DEG/ 08 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 291800Z --- 21.2S 108.9E 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 - 055 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 245 DEG/ 09 KTS --- 72 HRS, VALID AT: 301800Z --- 22.6S 105.3E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 272100Z POSITION NEAR 19.7S 115.8E. TROPICAL CYCLONE (TC) 03S (THREE), LOCATED APPROXIMATELY 212 NM NORTHEAST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS DEEPENING CENTRAL CONVECTION BEGINNING TO WRAP INTO THE LOW LEVEL CIRCULATION CENTER. THE CYCLONE HAS AN IMPRESSIVE SPIRAL BANDING SIGNATURE AND DAMPIER RADAR IMAGERY SHOWS A TIGHTENING CORE STRUCTURE. THE INITIAL INTENSITY HAS BEEN INCREASED TO 40 KNOTS BASED ON THE ABOVE STRUCTURAL IMPROVEMENTS AND WIND OBSERVATIONS FROM DAMPIER REACHING 37 KNOTS. TC 03S IS TRACKING SOUTHWESTWARD, PARALLEL TO THE NORTHWEST AUSTRALIAN COASTLINE. THE DOMINANT STEERING MECHANISM IS A DEEP LAYERED SUB-TROPICAL RIDGE (STR) POSITIONED OVER CENTRAL AUSTRALIA. ENVIRONMENTAL CONDITIONS ARE FAVORABLE WITH A DEEP CORE OF MOISTURE SUPPORTED BY LOW (5-10 KNOT) VERTICAL WIND SHEAR (VWS), STRONG DIVERGENCE ALOFT, AND WARM SEA SURFACE TEMPERATURES. THE ONLY HINDRANCE AT THIS TIME IS LAND INTERACTION DUE TO ITS PROXIMITY TO THE COASTLINE. THE CYCLONE WILL CONTINUE MOVING SOUTHWESTWARD UNDER THE STEERING STR THROUGHOUT THE FORECAST PERIOD. EXPECT A MODEST INTENSIFICATION TO 50 KNOTS AS THE CYCLONE CONTINUES TO FIGHT THE LAND INTERACTION. BEYOND TAU 36, VWS WILL BEGIN TO INCREASE DUE TO AN APPROACHING SHORT WAVE TROUGH AND SEA SURFACE TEMPERATURES WILL DROP BELOW 26 CELSIUS. THESE FACTORS WILL LEAD TO A STEADY WEAKENING UNTIL DISSIPATION BY TAU 72. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGHOUT THE FORECAST PERIOD, LEADING TO HIGH CONFIDENCE IN THE FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 271800Z IS 12 FEET. NEXT WARNINGS AT 280300Z, 280900Z, 281500Z AND 282100Z.//