SUBJ:  TROPICAL CYCLONE WARNING
WTPN32 PGTW 170900    
1. TYPHOON 25W (SONAMU) WARNING NR 013    
   01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
    ---
   WARNING POSITION:
   170600Z4 --- NEAR 33.0N6 142.1E8
     MOVEMENT PAST SIX HOURS - 015 DEGREES AT 21 KTS
     POSITION ACCURATE TO WITHIN 040 NM
     POSITION BASED ON EYE FIXED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
   RADIUS OF 050 KT WINDS - 060 NM EAST QUADRANT         
                            030 NM ELSEWHERE
   RADIUS OF 035 KT WINDS - 180 NM EAST QUADRANT         
                            065 NM ELSEWHERE
   REPEAT POSIT: 33.0N6 142.1E8
    ---
   FORECASTS:
   12 HRS, VALID AT:
   171800Z7 --- 36.9N8 143.8E6
   MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
   RADIUS OF 050 KT WINDS - 055 NM EAST QUADRANT         
                            025 NM ELSEWHERE
   RADIUS OF 035 KT WINDS - 175 NM EAST QUADRANT         
                            060 NM ELSEWHERE
   VECTOR TO 24 HR POSIT: 030 DEG/ 27 KTS
    ---
   24 HRS, VALID AT:
   180600Z5 --- 41.5N0 147.6E8
   MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
   BECOMING EXTRATROPICAL
   RADIUS OF 050 KT WINDS - 040 NM 
   RADIUS OF 035 KT WINDS - 140 NM SOUTHEAST SEMICIRCLE  
                            055 NM ELSEWHERE
   VECTOR TO 36 HR POSIT: 045 DEG/ 31 KTS
    ---
   36 HRS, VALID AT:
   181800Z8 --- 45.7N6 153.9E8
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   BECOMING EXTRATROPICAL
   VECTOR TO 48 HR POSIT: 060 DEG/ 36 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   190600Z6 --- 48.9N1 163.3E3
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   EXTRATROPICAL
    ---
REMARKS:
170900Z7 POSITION NEAR 34.0N7 142.5E2.
TYPHOON (TY) 25W (SONAMU), LOCATED APPROXIMATELY 190 NM SOUTHEAST OF
TOKYO, JAPAN, HAS TRACKED NORTH-NORTHEAST AT 21 KNOTS DURING 
THE PAST 6 HOURS. THE WARNING POSITION IS BASED ON 170530Z6 VISIBLE 
SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON SATELLITE 
CURRENT INTENSITY ESTIMATES OF 65 AND 77 KNOTS. ANIMATED VISIBLE
SATELLITE IMAGERY DEPICTS A 13 NM IRREGULAR EYE. ANIMATED IMAGERY 
ALSO DEPICTS IMPROVED ORGANIZATION NEAR THE SYSTEM CENTER OVER THE 
PAST 6 HOURS. ANIMATED WATER VAPOR IMAGERY INDICATES GOOD OUTFLOW IN 
ALL QUADRANTS EXCEPT FOR THE WESTERN QUADRANT. THE 170000Z8 500 MB
ANALYSIS INDICATES THAT THE MAJOR SHORTWAVE TROUGH HAS PROPAGATED
SLOWLY EASTWARD AND NOW EXTENDS FROM EASTERN MANCHURIA SOUTHWARD 
OVER EASTERN SOUTH KOREA THEN INTO EASTERN CHINA. A POLEWARD (NORTH-
SOUTH) ORIENTED RIDGE EAST OF TY 25W HAS ERODED SLIGHTLY, NORTH OF 
TY 25W, OVER THE LAST 12 HOURS. THEREFORE, TY 25W IS FORECAST TO 
TRACK NORTH-NORTHEASTWARD THROUGH THE NEXT 12 HOURS, THEN TO 
ACCELERATE NORTHEASTWARD THROUGH THE REMAINDER OF THE PERIOD AS THE 
MAJOR SHORT WAVE TROUGH PROPAGATES EASTWARD OVER THE SEA OF JAPAN. 
LITTLE CHANGE IN INTENSITY IS EXPECTED OVER THE NEXT 6-12 HOURS. 
AFTERWARD, INCREASING VERTICAL WIND SHEAR WILL SERVE TO WEAKEN THE 
SYSTEM AS IT BEGINS EXTRATROPICAL TRANSITION NEAR MID PERIOD. 
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 170600Z4 IS 21 FEET. REFER TO 
WWPW30 RJTX FOR ADDITIONAL SEA HEIGHT INFORMATION. NEXT WARNINGS AT 
171500Z4 (DTG 171352Z9), 172100Z1 (DTG 171952Z5), 180300Z2
(DTG 180152Z7) AND 180900Z8 (DTG 180752Z3).//