WTJP32 RJTD 121500 WARNING 121500. WARNING VALID 131500. STORM WARNING. SEVERE TROPICAL STORM 1507 DOLPHIN (1507) 985 HPA AT 09.9N 157.5E 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 131500UTC AT 10.3N 152.5E WITH 75 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 980 HPA, MAX WINDS 60 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=