WTXS31 PGTW 210300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 21S (GUAMBE) WARNING NR 008// RMKS/ 1. TROPICAL CYCLONE 21S (GUAMBE) WARNING NR 008 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 210000Z --- NEAR 28.6S 37.6E MOVEMENT PAST SIX HOURS - 145 DEGREES AT 14 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT 095 NM SOUTHEAST QUADRANT 065 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT REPEAT POSIT: 28.6S 37.6E --- FORECASTS: 12 HRS, VALID AT: 211200Z --- 30.5S 39.6E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 125 DEG/ 20 KTS --- 24 HRS, VALID AT: 220000Z --- 32.8S 43.5E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 170 NM SOUTHWEST QUADRANT 170 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 120 DEG/ 31 KTS --- 36 HRS, VALID AT: 221200Z --- 35.7S 50.2E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT 200 NM SOUTHEAST QUADRANT 220 NM SOUTHWEST QUADRANT 190 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 110 DEG/ 30 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 230000Z --- 37.8S 57.3E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 180 NM SOUTHWEST QUADRANT 140 NM NORTHWEST QUADRANT --- REMARKS: 210300Z POSITION NEAR 29.1S 38.1E. 21FEB21. TROPICAL CYCLONE 21S (GUAMBE), LOCATED APPROXIMATELY 409 NM SOUTH-SOUTHWEST OF EUROPA ISLAND, HAS TRACKED SOUTHEASTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRA-RED (EIR) SATELLITE IMAGERY INDICATES AN OVERALL SYMMETRICAL STRUCTURE WITH THE CENTRAL CONVECTION CONTINUING TO WARM AND FEEDER BANDS UNRAVELING. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON EXTRAPOLATION AND ADJUSTED SLIGHTLY FOR TILT, AND SPOT-ON WITH THE MICROWAVE EYE IN THE 202243Z AMSR2 PASS. THE INITIAL INTENSITY OF 65KTS IS HEDGED SLIGHTLY HIGHER THAN THE CURRENT INTENSITY DVORAK ESTIMATES OF T3.5/55KTS FROM PGTW AND FMEE AND CONSISTENT WITH THE EYE FEATURES IN THE MICROWAVE IMAGES. ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH LOW (10-15KT) VERTICAL WIND SHEAR (VWS), GOOD POLEWARD OUTFLOW ALOFT, AND WARM (28-29C) SST. GUAMBE HAS ROUNDED THE RIDGE AXIS AND IS TRACKING ALONG THE WEST-SOUTHWESTWARD PERIPHERY OF THE DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE EAST-NORTHEAST. TC 21S WILL BEGIN TO DECREASE IN INTENSITY AS IT ACCELERATES AND TRACKS SOUTHEASTWARD ON THE POLEWARD SIDE OF THE STR. INITIAL EXPOSURE TO THE STRONG MID-LATITUDE WESTERLIES WILL SLIGHTLY IMPROVE POLEWARD OUTFLOW AND TEMPORARILY INTENSIFY THE SYSTEM TO A PEAK OF 70 KTS BY TAU 24. AFTERWARD, INCREASING VWS AND COOLING SST WILL GRADUALLY ERODE THE SYSTEM DOWN TO 55KTS BY TAU 48. CONCURRENTLY, BY TAU 36, TC GUAMBE WILL BEGIN EXTRA-TROPICAL TRANSITION AS IT ENTERS THE BAROCLINIC ZONE, AND BECOME A STORM-FORCE COLD-CORE LOW BY TAU 48. NUMERICAL MODELS ARE IN TIGHT AGREEMENT, LENDING HIGH CONFIDENCE TO THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210000Z IS 21 FEET. NEXT WARNINGS AT 211500Z AND 220300Z.// NNNN