WTJP22 RJTD 290600 WARNING 290600. WARNING VALID 300600. WARNING IS UPDATED EVERY 6 HOURS. STORM WARNING. TROPICAL STORM 1618 CHABA (1618) 1000 HPA AT 14.7N 142.6E MARIANAS MOVING WEST 10 KNOTS. POSITION FAIR. MAX WINDS 35 KNOTS NEAR CENTER. RADIUS OF OVER 30 KNOT WINDS 90 MILES. FORECAST POSITION FOR 291800UTC AT 15.1N 140.5E WITH 30 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 996 HPA, MAX WINDS 40 KNOTS NEAR CENTER. FORECAST POSITION FOR 300600UTC AT 15.5N 138.4E WITH 50 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 990 HPA, MAX WINDS 50 KNOTS NEAR CENTER. EXTENDED OUTLOOK. FORECAST POSITION FOR 010600UTC AT 17.9N 135.1E WITH 95 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 975 HPA, MAX WINDS 65 KNOTS NEAR CENTER. FORECAST POSITION FOR 020600UTC AT 21.5N 131.6E WITH 140 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 955 HPA, MAX WINDS 80 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=