WTPN31 PGTW 012100 1. TROPICAL STORM 08W (CHATAAN) WARNING NR 016 02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE --- WARNING POSITION: 011800Z0 --- NEAR 7.2N9 154.9E9 MOVEMENT PAST SIX HOURS - 335 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT REPEAT POSIT: 7.2N9 154.9E9 --- FORECASTS: 12 HRS, VALID AT: 020600Z8 --- 8.1N9 153.9E8 MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT OVER WATER 070 NM SOUTHEAST QUADRANT OVER WATER 125 NM SOUTHWEST QUADRANT OVER WATER 125 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 310 DEG/ 11 KTS --- 24 HRS, VALID AT: 021800Z1 --- 9.5N4 152.3E1 MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT RADIUS OF 050 KT WINDS - 030 NM RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 310 DEG/ 11 KTS --- 36 HRS, VALID AT: 030600Z9 --- 11.0N2 150.6E2 MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT RADIUS OF 050 KT WINDS - 035 NM RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 085 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT 125 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 315 DEG/ 12 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 031800Z2 --- 12.6N9 148.9E2 MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT RADIUS OF 050 KT WINDS - 035 NM RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 115 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 305 DEG/ 12 KTS --- 72 HRS, VALID AT: 041800Z3 --- 15.4N0 144.8E7 MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT RADIUS OF 050 KT WINDS - 045 NM RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 125 NM SOUTHWEST QUADRANT OVER WATER 125 NM NORTHWEST QUADRANT --- REMARKS: 012100Z4 POSITION NEAR 7.4N1 154.6E6. TROPICAL STORM (TS) 08W (CHATAAN), LOCATED APPROXIMATELY 180 NM EAST OF CHUUK, HAS TRACKED NORTHWESTWARD AT 04 KNOTS OVER THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 011730Z2 INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE CURRENT INTENSITY ESTIMATES OF 45 AND 55 KNOTS. ANIMATED INFRARED SATELLITE IMAGERY INDICATES THAT THE DEEP CONVECTION CONTINUES TO CYCLE TO THE WEST OF THE LOW LEVEL CIRCULATION CENTER AND HAS INCREASED OVER THE PAST 6 HOURS. ANIMATED WATER VAPOR IMAGERY DEPICTS A SHORTWAVE TROUGH DEEPENING NORTH-NORTHWEST OF THE SYSTEM, WEAKENING THE RIDGE LOCATED WEST OF THE SYSTEM. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 011800Z0 IS 15 FEET. REFER TO WWPW31 RJTX FOR ADDITIONAL SEA HEIGHT INFORMATION. NEXT WARNINGS AT 020300Z5, 020900Z1, 021500Z8 AND 022100Z5. REFER TO TROPICAL STORM 09W (RAMMASUN) WARNINGS (WTPN32 PGTW) FOR SIX-HOURLY UPDATES.// NNNN