WTJP31 RJTD 140300 WARNING 140300. WARNING VALID 150300. STORM WARNING. TROPICAL STORM 1607 CHANTHU (1607) 994 HPA AT 22.1N 143.5E OGASAWARA SHOTO MOVING NORTHEAST 18 KNOTS. POSITION FAIR. MAX WINDS 40 KNOTS NEAR CENTER. RADIUS OF OVER 30 KNOT WINDS 180 MILES EAST SEMICIRCLE AND 90 MILES ELSEWHERE. FORECAST POSITION FOR 141500UTC AT 23.8N 144.6E WITH 40 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 990 HPA, MAX WINDS 45 KNOTS NEAR CENTER. FORECAST POSITION FOR 150300UTC AT 25.5N 144.5E WITH 60 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 985 HPA, MAX WINDS 50 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=