WTXS33 PGTW 120900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL CYCLONE 05S (JOYCE) WARNING NR 011 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 120600Z --- NEAR 19.8S 120.6E MOVEMENT PAST SIX HOURS - 230 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 025 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 - 125 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT REPEAT POSIT: 19.8S 120.6E --- FORECASTS: 12 HRS, VALID AT: 121800Z --- 21.1S 119.3E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 12 KTS --- 24 HRS, VALID AT: 130600Z --- 23.1S 117.9E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND VECTOR TO 36 HR POSIT: 210 DEG/ 14 KTS --- 36 HRS, VALID AT: 131800Z --- 25.4S 116.3E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 120900Z POSITION NEAR 20.1S 120.3E. TROPICAL CYCLONE 05S (JOYCE), LOCATED APPROXIMATELY 117 NM EAST- NORTHEAST OF PORT HEDLAND, AUSTRALIA, HAS TRACKED SOUTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A SYSTEM TRACKING ALONG THE COASTLINE OF WESTERN AUSTRALIA WITH STRONG CENTRAL CONVECTION AND LOOSELY ORGANIZED BANDING FEATURES. THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON SATELLITE FIXES AND ANIMATED RADAR IMAGERY. THE INITIAL INTENSITY IS ASSESSED AT 45 KNOTS WHICH IS BASED ON AN APRF DVORAK ESTIMATE OF T3.0 (45 KNOTS) AND A 120111Z OSCAT IMAGE SHOWING A REGION OF 40 TO 45 KNOTS ON THE WESTERN EDGE. RECENT OBSERVATIONS FROM MANDORA ARE REPORTING SUSTAINED WINDS ENE AT 30 KTS AND A SEA LEVEL PRESSURE OF 980MB FURTHER SUPPORTING BOTH THE INITIAL POSITION AND INTENSITY. ENVIRONMENTAL CONDITIONS ARE FAVORABLE WITH WARM SSTS AND A POINT SOURCE OVER TC 05S. A DEEP-LAYERED SUBTROPICAL RIDGE TO THE SOUTHEAST WILL STEER TC 05S ON A TRACK SOUTHWESTWARD OVER WESTERN AUSTRALIA. LAND INTERACTION WILL WEAKEN THE SYSTEM AND TC 05S WILL FULLY DISSIPATE OVER LAND BY TAU 36. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 120600Z IS 12 FEET. NEXT WARNINGS AT 121500Z, 122100Z, 130300Z AND 130900Z.//