WTJP21 RJTD 020000 WARNING 020000. WARNING VALID 030000. WARNING IS UPDATED EVERY 6 HOURS. STORM WARNING. SEVERE TROPICAL STORM 1604 NIDA (1604) 980 HPA AT 22.8N 113.6E SOUTH CHINA MOVING WESTNORTHWEST 12 KNOTS. POSITION GOOD. MAX WINDS 50 KNOTS NEAR CENTER. RADIUS OF OVER 30 KNOT WINDS 180 MILES EAST SEMICIRCLE AND 150 MILES ELSEWHERE. FORECAST POSITION FOR 021200UTC AT 24.0N 110.9E WITH 40 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 992 HPA, MAX WINDS 35 KNOTS. FORECAST POSITION FOR 030000UTC AT 24.7N 108.9E WITH 60 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 996 HPA. BECOMING TROPICAL DEPRESSION. JAPAN METEOROLOGICAL AGENCY.=