WTJP22 RJTD 291200 WARNING 291200. WARNING VALID 301200. WARNING IS UPDATED EVERY 6 HOURS. STORM WARNING. TROPICAL STORM 1618 CHABA (1618) 1000 HPA AT 13.5N 140.5E MARIANAS MOVING WESTSOUTHWEST 17 KNOTS. POSITION FAIR. MAX WINDS 35 KNOTS NEAR CENTER. RADIUS OF OVER 30 KNOT WINDS 90 MILES. FORECAST POSITION FOR 300000UTC AT 14.6N 138.9E WITH 30 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 996 HPA, MAX WINDS 40 KNOTS NEAR CENTER. FORECAST POSITION FOR 301200UTC AT 15.8N 137.2E WITH 50 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 990 HPA, MAX WINDS 50 KNOTS NEAR CENTER. EXTENDED OUTLOOK. FORECAST POSITION FOR 011200UTC AT 19.0N 133.6E WITH 110 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 975 HPA, MAX WINDS 65 KNOTS NEAR CENTER. FORECAST POSITION FOR 021200UTC AT 23.2N 130.0E WITH 140 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 955 HPA, MAX WINDS 80 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=