WDPN32 PGTW 021500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (TALAS) WARNING NR 
34//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
   A. TROPICAL STORM (TS) 15W (TALAS), LOCATED APPROXIMATELY 185 NM 
SOUTH-SOUTHWEST OF KYOTO, JAPAN, HAS TRACKED NORTH-NORTHWESTWARD AT 
10 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE 
IMAGERY INDICATES THAT TS 15W HAS BEGUN TO TRACK NORTHWARD AND MAKE 
LANDFALL. CONSEQUENTLY, CONVECTIVE CLOUD TOPS HAVE WARMED AND 
BANDING HAS BECOME MORE FRAGMENTED. AS EVIDENCED IN THE 020854Z 
CORIOLIS IMAGE AND JAPAN RADAR IMAGERY, THE SYSTEM HAS RETAINED A 
150-180 NM DIAMETER ANNULUS. JAPAN SURFACE OBSERVATIONS ALONG THE 
SOUTHEAST COAST OF SHIKOKU ARE REPORTING 40-45 KNOT WINDS. ANIMATED 
WATER VAPOR IMAGERY INDICATES IMPROVED POLEWARD OUTFLOW ENHANCED BY 
THE STRONG MIDLATITUDE WESTERLIES OVER THE EAST SEA. THERE IS GOOD 
CONFIDENCE IN THE CURRENT POSITION BASED ON THE RADAR IMAGERY AND 
FIXES FROM JAPAN. THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES 
RANGING FROM 35 TO 55 KNOTS. 
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY.
   B. TS 15W IS TRACKING ALONG THE WESTERN EDGE OF THE SUBTROPICAL 
STEERING RIDGE INTO THE WEAKNESS EVIDENT ON THE 02/00Z 500 MB 
ANALYSIS. FOR THE MOST PART, NUMERICAL MODEL GUIDANCE HAS COME INTO 
BETTER AGREEMENT WITH THE RE-CURVE SCENARIO, HOWEVER, THE JGSM, GFS 
AND WBAR MODELS CONTINUE TO DRIVE 15W INTO THE JET WHILE NOGAPS AND 
GFDN INDICATE SLOW AND ERRATIC TRACKS. THIS FORECAST FAVORS THE 
ECMWF AND UKMO MODELS IN ACCELERATING THE SYSTEM NORTHEASTWARD AS IT 
TRACKS INTO THE STRONG WESTERLY FLOW OVER THE EAST SEA. TS 15W IS 
EXPECTED TO BEGIN EXTRA-TROPICAL TRANSITION (ETT) BY TAU 12 AND 
SHOULD COMPLETE ETT BY TAU 48 WITH THE MODELS INDICATING A CLEAR 
FRONTAL SIGNATURE IN THE 1000/500 MB THICKNESS FIELDS.//
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