WTJP22 RJTD 011200 WARNING 011200. WARNING VALID 021200. WARNING IS UPDATED EVERY 6 HOURS. TYPHOON WARNING. TYPHOON 1618 CHABA (1618) UPGRADED FROM SEVERE TROPICAL STORM 970 HPA AT 17.6N 133.4E SEA EAST OF PHILIPPINES MOVING NORTHWEST 12 KNOTS. POSITION FAIR. MAX WINDS 70 KNOTS NEAR CENTER. RADIUS OF OVER 50 KNOT WINDS 50 MILES. RADIUS OF OVER 30 KNOT WINDS 150 MILES. FORECAST POSITION FOR 020000UTC AT 19.8N 131.4E WITH 40 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 960 HPA, MAX WINDS 75 KNOTS NEAR CENTER. FORECAST POSITION FOR 021200UTC AT 22.1N 129.6E WITH 60 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 955 HPA, MAX WINDS 80 KNOTS NEAR CENTER. EXTENDED OUTLOOK. FORECAST POSITION FOR 031200UTC AT 26.5N 128.1E WITH 110 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 950 HPA, MAX WINDS 85 KNOTS NEAR CENTER. FORECAST POSITION FOR 041200UTC AT 31.3N 129.0E WITH 220 MILES RADIUS OF 70 PERCENT PROBABILITY CIRCLE. 955 HPA, MAX WINDS 80 KNOTS NEAR CENTER. JAPAN METEOROLOGICAL AGENCY.=