WTPS51 PGTW 162100 WARNING ATCG MIL 11P SWP 160216200005 2016021618 11P WINSTON 015 01 070 12 SATL 060 T000 175S 1724W 075 R064 015 NE QD 030 SE QD 010 SW QD 020 NW QD R050 040 NE QD 050 SE QD 050 SW QD 040 NW QD R034 100 NE QD 120 SE QD 110 SW QD 120 NW QD T012 172S 1712W 090 R064 020 NE QD 020 SE QD 020 SW QD 020 NW QD R050 040 NE QD 040 SE QD 040 SW QD 040 NW QD R034 150 NE QD 150 SE QD 115 SW QD 115 NW QD T024 170S 1704W 095 R064 020 NE QD 020 SE QD 020 SW QD 020 NW QD R050 050 NE QD 050 SE QD 045 SW QD 050 NW QD R034 150 NE QD 150 SE QD 105 SW QD 105 NW QD T036 170S 1700W 100 R064 020 NE QD 020 SE QD 020 SW QD 020 NW QD R050 050 NE QD 050 SE QD 040 SW QD 045 NW QD R034 145 NE QD 145 SE QD 115 SW QD 115 NW QD T048 171S 1702W 110 R064 020 NE QD 020 SE QD 020 SW QD 020 NW QD R050 050 NE QD 050 SE QD 030 SW QD 030 NW QD R034 155 NE QD 155 SE QD 125 SW QD 125 NW QD T072 180S 1731W 110 R064 035 NE QD 035 SE QD 035 SW QD 035 NW QD R050 055 NE QD 050 SE QD 070 SW QD 050 NW QD R034 110 NE QD 125 SE QD 145 SW QD 130 NW QD T096 188S 1744W 100 T120 201S 1745W 095 AMP SUBJ: TROPICAL CYCLONE 11P (WINSTON) WARNING NR 015 1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 015 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 161800Z --- NEAR 17.5S 172.4W MOVEMENT PAST SIX HOURS - 070 DEGREES AT 12 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT REPEAT POSIT: 17.5S 172.4W --- FORECASTS: 12 HRS, VALID AT: 170600Z --- 17.2S 171.2W MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 075 DEG/ 04 KTS --- 24 HRS, VALID AT: 171800Z --- 17.0S 170.4W MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT 150 NM SOUTHEAST QUADRANT 105 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 090 DEG/ 02 KTS --- 36 HRS, VALID AT: 180600Z --- 17.0S 170.0W MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 045 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT 145 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 240 DEG/ 01 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 181800Z --- 17.1S 170.2W MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT 155 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 250 DEG/ 07 KTS --- 72 HRS, VALID AT: 191800Z --- 18.0S 173.1W MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 035 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 125 NM SOUTHEAST QUADRANT 145 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 235 DEG/ 04 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 201800Z --- 18.8S 174.4W MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT WIND RADII VALID OVER OPEN WATER ONLY VECTOR TO 120 HR POSIT: 185 DEG/ 03 KTS --- 120 HRS, VALID AT: 211800Z --- 20.1S 174.5W MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY --- REMARKS: 162100Z POSITION NEAR 17.4S 172.1W. TROPICAL CYCLONE 11P (WINSTON), LOCATED APPROXIMATELY 216 NM SOUTH-SOUTHWEST OF PAGO PAGO, HAS TRACKED EAST-NORTHEASTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS DEEP CONVECTION IMPROVING SINCE THE PREVIOUS WARNING, WITH OVERSHOOTING COLD CONVECTIVE TOPS WRAPPING INTO A CENTRAL DENSE OVERCAST. A 161812Z SSMIS 91 GHZ MICROWAVE IMAGE DEPICTS CENTRAL CONVECTION COMPLETELY SURROUNDING A WELL- DEFINED MICROWAVE EYE FEATURE, GIVING HIGH CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 75 KNOTS BASED ON DVORAK ESTIMATES FROM PGTW REPORTING T4.5. ENVIRONMENTAL ANALYSIS INDICATES THAT TC WINSTON IS CURRENTLY TRACKING IN AN AREA THAT IS ADVANTAGEOUS FOR FURTHER INTENSIFICATION WITH FAVORABLE SEA SURFACE TEMPERATURES (30 CELSIUS), LOW TO MODERATE (15 TO 20 KNOTS) VERTICAL WIND SHEAR AND A STRONG POLEWARD OUTFLOW CHANNEL. THE PRIMARY STEERING MECHANISM IS A DEEP-LAYER NEAR-EQUATORIAL RIDGE TO THE NORTH, WHICH WILL CONTINUE TO STEER TC WINSTON ON ITS CURRENT EAST- NORTHEASTWARD TRACK THROUGH TAU 24. BETWEEN TAUS 24 AND 48, AS THE WESTERN RIDGE BUILDS TO THE SOUTH OF THE TC, A DEEP-LAYER SUBTROPICAL RIDGE (STR) WILL BUILD IN TO THE EAST, CAUSING TC WINSTON TO RAPIDLY SLOW ITS FORWARD MOVEMENT, ULTIMATELY BECOMING QUASI-STATIONARY BY TAU 48. AFTER TAU 48, UNDER THE COMBINED INFLUENCE OF THE TWO AFOREMENTIONED RIDGES, TC WINSTON WILL TRANSLATE TO A WEST-SOUTHWESTWARD TRACK THROUGH TAU 96. AFTERWARDS, THE TRACK WILL BECOME MORE SOUTHWARD, TRACKING TOWARDS A WEAKNESS IN THE STR AHEAD OF AN ADVANCING MID-LATITUDE TROUGH. ENVIRONMENTAL CONDITIONS WILL REMAIN FAVORABLE FOR INTENSIFICATION, AND TC WINSTON IS EXPECTED TO REACH 110 KNOTS BY TAU 48. DUE TO THE UNCERTAINTY IN THE OVERALL SYNOPTIC ENVIRONMENT, DYNAMIC MODEL GUIDANCE IS IN DISAGREEMENT BEYOND TAU 24, AS THE CYCLONE BECOMES QUASI-STATIONARY, BUT HAS COME INTO BETTER AGREEMENT OVER THE PAST 12 HOURS IN FORECASTING THE TURN TO THE WEST. DUE TO THIS UNCERTAINTY, THERE IS LOW CONFIDENCE TO THE JTWC FORECAST TRACK BEYOND TAU 24. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 161800Z IS 28 FEET. NEXT WARNINGS AT 170900Z AND 172100Z.// 1116020818 111S1680E 20 1116020900 117S1686E 20 1116020906 123S1689E 20 1116020912 130S1692E 20 1116020918 136S1695E 20 1116021000 141S1700E 25 1116021006 145S1704E 30 1116021012 149S1707E 35 1116021018 153S1709E 40 1116021100 157S1711E 40 1116021106 161S1714E 45 1116021112 167S1716E 55 1116021112 167S1716E 55 1116021118 174S1716E 55 1116021118 174S1716E 55 1116021200 180S1716E 65 1116021200 180S1716E 65 1116021206 187S1716E 95 1116021206 187S1716E 95 1116021206 187S1716E 95 1116021212 197S1715E 105 1116021212 197S1715E 105 1116021212 197S1715E 105 1116021218 208S1715E 110 1116021218 208S1715E 110 1116021218 208S1715E 110 1116021300 222S1718E 105 1116021300 222S1718E 105 1116021300 222S1718E 105 1116021306 233S1722E 100 1116021306 233S1722E 100 1116021306 233S1722E 100 1116021312 242S1728E 95 1116021312 242S1728E 95 1116021312 242S1728E 95 1116021318 247S1736E 90 1116021318 247S1736E 90 1116021318 247S1736E 90 1116021400 253S1749E 75 1116021400 253S1749E 75 1116021400 253S1749E 75 1116021406 254S1765E 70 1116021406 254S1765E 70 1116021406 254S1765E 70 1116021412 248S1776E 65 1116021412 248S1776E 65 1116021418 241S1788E 65 1116021418 241S1788E 65 1116021500 230S1796E 60 1116021500 230S1796E 60 1116021506 218S1795W 55 1116021506 218S1795W 55 1116021512 206S1781W 50 1116021518 198S1767W 40 1116021600 190S1755W 45 1116021606 185S1745W 55 1116021606 185S1745W 55 1116021612 179S1736W 65 1116021612 179S1736W 65 1116021618 175S1724W 75 1116021618 175S1724W 75 1116021618 175S1724W 75 NNNN