WTJP31 RJTD 132100 WARNING 132100. WARNING VALID 142100. STORM WARNING. TROPICAL STORM 1607 CHANTHU (1607) 998 HPA AT 20.2N 142.1E OGASAWARA SHOTO MOVING NORTHEAST 10 KNOTS. POSITION FAIR. MAX WINDS 35 KNOTS NEAR CENTER. RADIUS OF OVER 30 KNOT WINDS 180 MILES SOUTHEAST SEMICIRCLE AND 90 MILES ELSEWHERE. FORECAST POSITION FOR 140900UTC AT 22.2N 144.0E WITH 40 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 992 HPA, MAX WINDS 40 KNOTS NEAR CENTER. FORECAST POSITION FOR 142100UTC AT 24.3N 144.7E WITH 80 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 985 HPA, MAX WINDS 50 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=