WTJP32 RJTD 040300 WARNING 040300. WARNING VALID 050300. TYPHOON WARNING. SEVERE TROPICAL STORM 1813 SHANSHAN (1813) 985 HPA AT 20.5N 148.9E SEA AROUND OF MINAMITORISIMA MOVING NORTHNORTHWEST 08 KNOTS. POSITION FAIR. MAX WINDS 55 KNOTS NEAR CENTER. RADIUS OF OVER 50 KNOT WINDS 40 MILES. RADIUS OF OVER 30 KNOT WINDS 300 MILES SOUTH SEMICIRCLE AND 150 MILES ELSEWHERE. FORECAST POSITION FOR 041500UTC AT 22.2N 147.7E WITH 30 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 980 HPA, MAX WINDS 60 KNOTS NEAR CENTER. FORECAST POSITION FOR 050300UTC AT 23.8N 146.7E WITH 50 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 970 HPA, MAX WINDS 70 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=