WDPN31 PGTW 251500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 19W (PABUK) WARNING NR 19//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON 19W (PABUK), LOCATED APPROXIMATELY 307 NM SOUTH OF
YOKOSUKA, JAPAN, HAS TRACKED NORTHEASTWARD AT 13 KNOTS OVER THE
PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY ALONG 
WITH A 251116Z AMSU-B MICROWAVE IMAGE REVEALS DEEP CONVECTION AROUND 
THE EYEWALL HAS STARTED TO SLIGHTLY SHALLOW AS THE EYE HAS INCREASED 
TO 40NM WHILE A BANDING FEATURE HAS STARTED TO FORM IN THE NORTHWEST 
QUADRANT. THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON 
THE EYE FEATURE SEEN IN THE AFOREMENTIONED SATELLITE IMAGERY. THE 
INITIAL INTENSITY HAS BEEN HELD AT 90 KNOTS BASED ON DVORAK CURRENT 
INTENSITY ESTIMATES FROM PGTW AND KNES. UPPER LEVEL ANALYSIS 
INDICATES A POINT-SOURCE ANTICYCLONE REMAINS OVER THE SYSTEM WHICH 
IS PROVIDING FAVORABLE RADIAL OUTFLOW, WITH ENHANCED POLEWARD 
OUTFLOW DUE TO STRONG MID-LATITUDE WESTERLIES OVER JAPAN. TY 19W HAS 
ROUNDED THE SUBTROPICAL RIDGE (STR) AXIS AND IS NOW ACCELERATING TO 
THE NORTHEAST ALONG THE NORTHWESTERN PERIPHERY OF THE STR.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS 
PROGNOSTIC REASONING MESSAGE.
   B. TY 19W IS FORECAST TO CONTINUE TO ACCELERATE TO THE NORTHEAST 
UNDER THE INFLUENCE OF THE STR TO THE SOUTHEAST AND A PRESSING MID-
LATITUDE TROUGH THAT IS CURRENTLY LOCATED OVER JAPAN. THIS 
APPROACHING MID-LATITUDE TROUGH WILL BEGIN TO DEGRADE THE FAVORABLE 
UPPER-LEVEL ENVIRONMENT AS INCREASING VERTICAL WIND SHEAR AND COLD 
AIR ENTRAINMENT BEGINS TO IMPACT THE SYSTEM. EXTRA-TROPICAL 
TRANSITION IS EXPECTED TO BEGIN AROUND TAU 24 AND COMPLETE BY TAU 48 
AS THE SYSTEM BECOMES A STRONG COLD-CORE LOW. MODEL GUIDANCE REMAINS 
IN VERY TIGHT AGREEMENT THROUGHOUT THE FORECAST, LEADING TO HIGH 
CONFIDENCE IN THE FORECAST TRACK.//
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