WTXS31 PGTW 191500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 06S (BERGUITTA) WARNING NR 028// RMKS/ 1. TROPICAL CYCLONE 06S (BERGUITTA) WARNING NR 028 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 191200Z --- NEAR 25.0S 52.7E MOVEMENT PAST SIX HOURS - 210 DEGREES AT 14 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 230 NM SOUTHEAST QUADRANT 205 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT REPEAT POSIT: 25.0S 52.7E --- FORECASTS: 12 HRS, VALID AT: 200000Z --- 27.7S 51.2E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT 285 NM SOUTHEAST QUADRANT 245 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 190 DEG/ 14 KTS --- 24 HRS, VALID AT: 201200Z --- 30.4S 50.7E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 265 NM SOUTHEAST QUADRANT 220 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 165 DEG/ 09 KTS --- 36 HRS, VALID AT: 210000Z --- 32.2S 51.3E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 215 NM NORTHEAST QUADRANT 265 NM SOUTHEAST QUADRANT 215 NM SOUTHWEST QUADRANT 145 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 125 DEG/ 07 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 211200Z --- 33.0S 52.7E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT 275 NM SOUTHEAST QUADRANT 220 NM SOUTHWEST QUADRANT 170 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 115 DEG/ 10 KTS --- 72 HRS, VALID AT: 221200Z --- 34.7S 57.3E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 034 KT WINDS - 185 NM NORTHEAST QUADRANT 275 NM SOUTHEAST QUADRANT 295 NM SOUTHWEST QUADRANT 245 NM NORTHWEST QUADRANT --- REMARKS: 191500Z POSITION NEAR 25.7S 52.3E. TROPICAL CYCLONE 06S (BERGUITTA), LOCATED APPROXIMATELY 306 NM SOUTH-SOUTHWEST OF ST DENIS, HAS TRACKED SOUTH-SOUTHWESTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS CONVECTIVE BANDING WRAPPING INTO A CENTRALLY LOCATED AREA OF DEEP CONVECTION THAT IS OBSCURING THE LOW-LEVEL CIRCULATION CENTER (LLCC). THE CURRENT POSITION IS BASED ON THE PGTW SATELLITE IMAGERY FIX AND IS SUPPORTED BY A 191157Z 89GHZ AMSU MICROWAVE IMAGE. THE INITIAL INTENSITY OF 50 KNOTS IS BASED ON MULTI-AGENCY CURRENT INTENSITY ESTIMATES RANGING FROM T3.0 TO T3.5 (45-55 KNOTS) FROM PGTW AND KNES RESPECTIVELY. THE SYSTEM HAS WEAKENED OVER THE PAST 6 HOURS DUE TO INCREASED NORTHEASTERLY VERTICAL WIND SHEAR. TC 06S IS CURRENTLY TRACKING TO THE SOUTHWEST ALONG THE PERIPHERY OF A SUBTROPICAL RIDGE POSITIONED TO THE SOUTHEAST. ENVIRONMENTAL ANALYSIS SHOWS THE SYSTEM IS IN AN AREA OF LOW TO MODERATE (10-15 KNOTS) VERTICAL WIND SHEAR, HAS STRONG POLEWARD OUTFLOW ENHANCED BY THE MID-LATITUDE WESTERLIES, AND IS TRACKING THROUGH AN AREA OF WARM (26-27 CELSIUS) SEA SURFACE TEMPERATURES. THE SYSTEM IS FORECAST TO CONTINUE TO TRACK TO THE SOUTH-SOUTHWEST THROUGH TAU 24 AT WHICH POINT 06S WILL ROUND THE RIDGE AXIS AND RECURVE TO THE SOUTHEAST. AROUND TAU 12, INCREASING VERTICAL WIND SHEAR COMBINED WITH COOLER (<26 CELSIUS) SEA SURFACE TEMPERATURES WILL FURTHER WEAKEN THE SYSTEM. TC BERGUITTA IS FORECAST TO BEGIN EXTRA-TROPICAL TRANSITION (ETT) SHORTLY AFTER TAU 24 AND COMPLETE ETT BY TAU 72. THE SYSTEM WILL MAINTAIN AN EXPANSIVE GALE FORCE WIND FIELD IN THE EXTENDED RANGE DUE TO FAVORABLE INTERACTION WITH THE BAROCLINIC ZONE THROUGHOUT ETT. AVAILABLE DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 191200Z IS 14 FEET. NEXT WARNINGS AT 192100Z, 200300Z, 200900Z AND 201500Z. //