WTXS31 PGTW 102100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 05S (FIVE) WARNING NR 002// RMKS/ 1. TROPICAL CYCLONE 05S (FIVE) WARNING NR 002 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 101800Z --- NEAR 15.6S 69.4E MOVEMENT PAST SIX HOURS - 200 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 060 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 - 055 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT REPEAT POSIT: 15.6S 69.4E --- FORECASTS: 12 HRS, VALID AT: 110600Z --- 16.6S 68.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 075 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 225 DEG/ 07 KTS --- 24 HRS, VALID AT: 111800Z --- 17.5S 67.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 220 DEG/ 08 KTS --- 36 HRS, VALID AT: 120600Z --- 18.7S 66.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 210 DEG/ 10 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 121800Z --- 20.4S 65.7E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 200 DEG/ 11 KTS --- 72 HRS, VALID AT: 131800Z --- 24.6S 63.9E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 102100Z POSITION NEAR 15.9S 69.2E. TROPICAL CYCLONE 05S (FIVE), LOCATED APPROXIMATELY 542 NM SOUTH- SOUTHWEST OF DIEGO GARCIA, HAS TRACKED SOUTH-SOUTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS A TIGHTLY WRAPPED LOW LEVEL CIRCULATION CENTER (LLCC) WITH DEEP CONVECTION BECOMING MORE FRAGMENTED AND DISORGANIZED OVER THE PREVIOUS 12 HOURS. A RECENT 101725Z 89 GHZ AMSU IMAGE REVEALS THE STRONGEST CONVECTION HAS DIMINISHED IN MOST QUADRANTS EXCEPT FOR THE WESTERN PERIPHERY. SCATTEROMETRY DATA FROM A 101726Z ASCAT-B PASS DEPICTS A FAIRLY SYMMETRIC LLCC WITH 25 TO 35 KNOT WINDS SURROUNDING THE SYSTEM, AND ISOLATED 40 KNOT WINDS WITHIN THE CONVECTION TO THE SOUTHEAST OF THE CENTER. UPPER LEVEL ANALYSIS INDICATES A MARGINALLY- FAVORABLE ENVIRONMENT FOR FURTHER DEVELOPMENT WITH LOW VERTICAL WIND SHEAR (10-15 KNOTS) AND GOOD POLEWARD OUTFLOW. OUTFLOW HAS ALSO IMPROVED ON THE NORTHERN PERIPHERY OF THE SYSTEM OVER THE LAST SEVERAL HOURS. SEA SURFACE TEMPERATURES IN THE VICINITY OF TC 05S ARE MARGINAL FOR FURTHER DEVELOPMENT (27 CELSIUS), BUT THEY TOO WILL BECOME UNFAVORABLE AFTER TAU 48, LEADING TO A WEAKENING OF THE SYSTEM. TC 05S IS TRACKING GENERALLY SOUTHWARD ALONG THE WESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR), BUT MODEL GUIDANCE INDICATES THAT THE STR WILL BEGIN TO SHIFT WESTWARD AND NUDGE TC 05S SOUTHWESTWARD DURING THE FORECAST PERIOD. PASSAGE OVER COOLER WATER AND INCREASING INTERACTION WITH UPPER-LEVEL WESTERLY FLOW WILL RESULT IN DISSIPATION OF THE SYSTEM BY TAU 72. MODEL GUIDANCE IS IN FAIR AGREEMENT WITH THIS SCENARIO; HOWEVER THERE ARE SOME DISPARITIES IN THE TIMING, INTENSITY, AND MOVEMENT OF 05S, AS IT INTERACTS WITH THE RIDGE. GIVEN THESE VARIABLES THE CURRENT FORECAST LIES CLOSE TO THE MULTI-MODEL CONSENSUS, WITH LOW CONFIDENCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 101800Z IS 14 FEET. NEXT WARNINGS AT 110900Z AND 112100Z.//