WTXS31 PGTW 182100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 06S (BERGUITTA) WARNING NR 025// RMKS/ 1. TROPICAL CYCLONE 06S (BERGUITTA) WARNING NR 025 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 181800Z --- NEAR 22.4S 54.8E MOVEMENT PAST SIX HOURS - 240 DEGREES AT 19 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY A COMBINATION OF SATELLITE AND RADAR PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT 235 NM SOUTHEAST QUADRANT 200 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT REPEAT POSIT: 22.4S 54.8E --- FORECASTS: 12 HRS, VALID AT: 190600Z --- 23.9S 52.8E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 105 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 280 NM SOUTHEAST QUADRANT 255 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 12 KTS --- 24 HRS, VALID AT: 191800Z --- 25.8S 51.3E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 265 NM SOUTHEAST QUADRANT 230 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 200 DEG/ 13 KTS --- 36 HRS, VALID AT: 200600Z --- 28.3S 50.4E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 055 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 205 NM NORTHEAST QUADRANT 255 NM SOUTHEAST QUADRANT 215 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 175 DEG/ 13 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 201800Z --- 30.8S 50.7E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 205 NM NORTHEAST QUADRANT 240 NM SOUTHEAST QUADRANT 210 NM SOUTHWEST QUADRANT 145 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 140 DEG/ 07 KTS --- 72 HRS, VALID AT: 211800Z --- 33.1S 52.9E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT 250 NM SOUTHEAST QUADRANT 240 NM SOUTHWEST QUADRANT 185 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 120 DEG/ 12 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 221800Z --- 35.5S 57.8E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 280 NM SOUTHEAST QUADRANT 270 NM SOUTHWEST QUADRANT 215 NM NORTHWEST QUADRANT --- REMARKS: 182100Z POSITION NEAR 22.8S 54.3E. TROPICAL CYCLONE 06S (BERGUITTA), LOCATED APPROXIMATELY 117 NM SOUTH-SOUTHWEST OF ST DENIS, HAS TRACKED WEST-SOUTHWESTWARD AT 19 KNOTS OVER THE PAST SIX HOURS. RECENT ANIMATED INFRARED SATELLITE IMAGERY SHOWS A CENTRAL CONVECTIVE MASS COVERING THE LOW-LEVEL CIRCULATION CENTER. RADAR IMAGERY FROM LA REUNION AND A 1533Z SSMIS 37GHZ MICROWAVE IMAGE SHOW A WELL-DEFINED CENTER FEATURE, AND THE CURRENT POSITION IS BASED ON THESE SOURCES AS WELL AS A 1737Z ASCAT PASS. THE INTENSITY OF 60 KNOTS IS SLIGHTLY HIGHER THAN DVORAK CURRENT INTENSITY ESTIMATES RANGING FROM T3.0 TO T3.5 (45-55 KNOTS) FROM KNES AND PGTW, RESPECTIVELY, AND IS SUPPORTED BY RECENT AUTOMATED SATELLITE INTENSITY CONSENSUS ESTIMATES. THE SYSTEM HAS WEAKENED SLIGHLTY OVER THE PAST SIX HOURS, WITH WARMING CONVECTIVE TOPS EVIDENT IN INFRARED SATELLITE DATA CONFIRMING THE WEAKENING TREND. TC 06S IS TURNING POLEWARD ALONG THE PERIPHERY OF A STEERING RIDGE SITUATED TO THE SOUTH AND EAST, AND IS EXPECTED TO CONTINUE TRACKING AROUND THE RIDGE THROUGHOUT THE FORECAST PERIOD. AN UPPER- LEVEL ANTICYCLONE OVER TC 06S HAS RESULTED IN DECREASING VERTICAL WIND SHEAR OVER THE SYSTEM. HOWEVER, SHEAR IS EXPECTED TO INCREASE SLIGHTLY, AND ALONG-TRACK SEA SURFACE TEMPERATURES ARE EXPECTED TO DECREASE, INDUCING A SLOW WEAKENING TREND IN THE NEAR TO MEDIUM- TERM. BY TAU 48, TC 06S WILL BEGIN EXTRATROPICAL TRANSITION, AND FAVORABLE INTERACTION WITH THE BAROCLINIC ZONE WILL ENABLE THE SYSTEM TO MAINTAIN INTENSITY AROUND 45 KNOTS AS IT COMPLETES EXTRATROPICAL TRANSITION BY TAU 96. NUMERICAL MODELS ARE IN EXCELLENT AGREEMENT REGARDING THE TRACK AND INTENSITY, LENDING HIGH CONFIDENCE TO THE CURRENT FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 181800Z IS 16 FEET. NEXT WARNINGS AT 190300Z, 190900Z, 191500Z AND 192100Z.//