WTXS31 PGTW 301500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 21S (HELLEN) WARNING NR 005// RMKS/ 1. TROPICAL CYCLONE 21S (HELLEN) WARNING NR 005 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 301200Z --- NEAR 14.7S 44.6E MOVEMENT PAST SIX HOURS - 135 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 010 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT REPEAT POSIT: 14.7S 44.6E --- FORECASTS: 12 HRS, VALID AT: 310000Z --- 15.3S 45.1E MAX SUSTAINED WINDS - 140 KT, GUSTS 170 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 180 DEG/ 04 KTS --- 24 HRS, VALID AT: 311200Z --- 16.1S 45.1E MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT 115 NM SOUTHEAST QUADRANT 095 NM SOUTHWEST QUADRANT 095 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 235 DEG/ 04 KTS --- 36 HRS, VALID AT: 010000Z --- 16.5S 44.5E MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 085 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 245 DEG/ 04 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 011200Z --- 16.8S 43.8E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 090 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 255 DEG/ 05 KTS --- 72 HRS, VALID AT: 021200Z --- 17.2S 41.9E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 085 NM SOUTHWEST QUADRANT 075 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 265 DEG/ 05 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 031200Z --- 17.4S 39.8E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 120 HR POSIT: 275 DEG/ 06 KTS --- 120 HRS, VALID AT: 041200Z --- 17.2S 37.3E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY --- REMARKS: 301500Z POSITION NEAR 14.9S 44.7E. TROPICAL CYCLONE (TC) 21S (HELLEN), LOCATED APPROXIMATELY 290 NM NORTH-NORTHWEST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. TC 21S HAS RAPIDLY INTENSIFIED 80 KNOTS OVER THE PAST 24 HOURS, FROM 50 KNOTS TO THE CURRENT INTENSITY OF 130 KNOTS, WHICH IS BASED ON DVORAK INTENSITY ESTIMATES OF T6.5 (127 KNOTS) FROM ALL AGENCIES. ANIMATED INFRARED SATELLITE IMAGERY DEPICTS AN 11-NM ROUND EYE SURROUNDED BY A NEAR-SYMMETRIC, 130 NM DIAMETER EYEWALL. THE RAPID INTENSIFICATION PHASE HAS BEEN FUELED BY EXCELLENT RADIAL OUTFLOW, EVIDENT IN ANIMATED WATER VAPOR IMAGERY, AND FAVORABLE ENVIRONMENTAL CONDITIONS. DESPITE WEAKENING OF OUTER CONVECTIVE BANDING DUE TO LAND INTERACTION, A 301146Z SSMI IMAGE INDICATES THAT THE SYSTEM HAS MAINTAINED AN INTENSE CORE OF CENTRAL CONVECTION. TC 21S IS TRACKING SLOWLY SOUTHEASTWARD BUT IS FORECAST TO TURN SOUTHWARD BY TAU 24 AS IT TRACKS ALONG THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR). AFTER TAU 24, TC HELLEN WILL TURN WESTWARD AS THE STR BUILDS TO THE SOUTH AND IS FORECAST TO MAKE LANDFALL OVER MOZAMBIQUE BY TAU 120. DYNAMIC GUIDANCE IS IN FAIR AGREEMENT WITH THE EXCEPTION OF NAVGEM, WHICH ERRONEOUSLY DRIVES THE SYSTEM SOUTH-SOUTHWESTWARD INTO THE STR. DESPITE THE GENERAL AGREEMENT ON THE FORECAST TRACK, FORECAST CONFIDENCE REMAINS LOW DUE TO TIMING AND DEGREE OF THE WESTWARD TURN WITH LAND INTERACTION FURTHER COMPLICATING THE SHORT- TERM TRACK. TC 21S IS FORECAST TO CONTINUE INTENSIFYING TO A PEAK INTENSITY OF 140 KNOTS BY TAU 12 (IN FACT, 1230Z IMAGERY SUPPORTS A T7.0 WHICH EQUATES TO 140 KNOTS). NEAR TAU 12, THE SYSTEM CORE IS EXPECTED TO BEGIN INTERACTING WITH LAND, WHICH SHOULD RESULT IN A SHARP WEAKENING TREND THROUGH TAU 48. FURTHER WEAKENING IS EXPECTED AS THE SYSTEM APPROACHES THE MOZAMBIQUE COAST AND ENCOUNTERS DRY AIR ENTRAINMENT. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 301200Z IS 35 FEET. NEXT WARNINGS AT 310300Z AND 311500Z.// NNNN