WTJP31 RJTD 010900 WARNING 010900. WARNING VALID 020900. TYPHOON WARNING. SEVERE TROPICAL STORM 1604 NIDA (1604) 975 HPA AT 21.7N 117.0E SOUTH CHINA SEA MOVING NORTHWEST 14 KNOTS. POSITION GOOD. MAX WINDS 60 KNOTS NEAR CENTER. RADIUS OF OVER 50 KNOT WINDS 60 MILES. RADIUS OF OVER 30 KNOT WINDS 180 MILES. FORECAST POSITION FOR 012100UTC AT 22.8N 114.5E WITH 40 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 965 HPA, MAX WINDS 70 KNOTS NEAR CENTER. FORECAST POSITION FOR 020900UTC AT 23.6N 111.8E WITH 60 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 975 HPA, MAX WINDS 60 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=