WTJP31 RJTD 281500 WARNING 281500. WARNING VALID 291500. STORM WARNING. TROPICAL STORM 1821 JEBI (1821) 1000 HPA AT 16.7N 154.9E SEA AROUND OF MINAMITORISIMA MOVING WESTNORTHWEST 09 KNOTS. POSITION FAIR. MAX WINDS 40 KNOTS NEAR CENTER. RADIUS OF OVER 30 KNOT WINDS 120 MILES EAST SEMICIRCLE AND 90 MILES ELSEWHERE. FORECAST POSITION FOR 290300UTC AT 17.4N 152.9E WITH 30 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 996 HPA, MAX WINDS 50 KNOTS NEAR CENTER. FORECAST POSITION FOR 291500UTC AT 17.6N 150.9E WITH 50 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 990 HPA, MAX WINDS 60 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=