WTJP32 RJTD 120300 WARNING 120300. WARNING VALID 130300. STORM WARNING. SEVERE TROPICAL STORM 1507 DOLPHIN (1507) 985 HPA AT 10.1N 158.1E MARSHALLS MOVING WEST SLOWLY. POSITION FAIR. MAX WINDS 55 KNOTS NEAR CENTER. RADIUS OF OVER 50 KNOT WINDS 50 MILES. RADIUS OF OVER 30 KNOT WINDS 150 MILES. FORECAST POSITION FOR 130300UTC AT 10.2N 154.2E WITH 70 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 985 HPA, MAX WINDS 55 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=