WTPN31 PGTW 181500 1. TROPICAL STORM 20W (VONGFONG) WARNING NR 013 02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE --- WARNING POSITION: 181200Z2 --- NEAR 16.7N4 111.6E9 MOVEMENT PAST SIX HOURS - 280 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT REPEAT POSIT: 16.7N4 111.6E9 --- FORECASTS: 12 HRS, VALID AT: 190000Z0 --- 17.5N3 111.2E5 MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 360 DEG/ 07 KTS --- 24 HRS, VALID AT: 191200Z3 --- 18.9N8 111.2E5 MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT OVER WATER VECTOR TO 36 HR POSIT: 350 DEG/ 07 KTS --- 36 HRS, VALID AT: 200000Z2 --- 20.3N5 110.9E1 MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT OVER WATER 055 NM NORTHWEST QUADRANT OVER WATER VECTOR TO 48 HR POSIT: 330 DEG/ 08 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 201200Z5 --- 21.7N0 110.1E3 MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT VECTOR TO 72 HR POSIT: 315 DEG/ 08 KTS --- 72 HRS, VALID AT: 211200Z6 --- 24.0N6 107.7E5 MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 181500Z5 POSITION NEAR 16.9N6 111.5E8. TROPICAL STORM (TS) 20W (VONGFONG), LOCATED APPROXIMATELY 365 NM SOUTH-SOUTHWEST OF HONG KONG, CHINA, HAS TRACKED WEST-NORTHWESTWARD AT 06 KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 181130Z6 ENHANCED INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 30 AND 35 KNOTS AND SYNOPTIC OBSERVATIONS. ANIMATED ENHANCED INFRARED IMAGERY INDICATES INCREASING DEEP CONVECTION OVER THE LOW LEVEL CIRCULATION CENTER AND A WEAK RAIN BANDS FORMING IN THE NORTHERN SEMI-CIRCLE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 181200Z2 IS 20 FEET. REFER TO WWPW31 RJTX FOR ADDITIONAL SEA HEIGHT INFORMATION. NEXT WARNINGS AT 182100Z2, 190300Z3, 190900Z9 AND 191500Z6. REFER TO TYPHOON 19W (PHANFONE) WARNINGS (WTPN32 PGTW) FOR SIX-HOURLY UPDATES.// NNNN