MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (LINGLING) WARNING NR 05// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 15W (LINGLING), LOCATED APPROXIMATELY 451 NM SOUTH-SOUTHWEST OF KADENA AB, HAS TRACKED NORTH-NORTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS IMPRESSIVE DEEP CONVECTIVE BANDING WRAPPING AROUND THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE AND IS BASED ON A 022255Z SSMIS 37GHZ MICROWAVE IMAGE, WHICH SHOWS A WELL DEFINED CIRCULATION. THE INITIAL INTENSITY OF 50 KNOTS IS HEDGED BETWEEN DVORAK CURRENT INTENSITY (CI) ESTIMATES OF T3.0 (45 KNOTS) FROM RJTD AND T3.5 (55 KNOTS) FROM PGTW. ENVIRONMENTAL ANALYSIS SHOWS TS 15W IS EXPERIENCING FAVORABLE (5 TO 10 KNOT) VERTICAL WIND SHEAR. THERE IS A STRONG EQUATORWARD OUTFLOW CHANNEL, WHILE THE POLEWARD OUTFLOW CHANNEL CONTINUES TO DEVELOP. SEA SURFACE TEMPERATURES ARE FAVORABLE FOR ADDITIONAL DEVELOPMENT, NEAR 30 DEGREES CELSIUS. TS 15W IS TRACKING NORTHWARD WHILE UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE (STR), LOCATED TO THE EAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THE STR LOCATED TO THE EAST WILL BE THE PRIMARY STEERING FEATURE FOR TS 15W THROUGH TAU 72. FAVORABLE SEA SURFACE TEMPERATURES AND FAVORABLE VERTICAL WIND SHEAR WILL ALLOW TS 15W TO QUICKLY INTENSIFY, REACHING 85 KNOTS BY TAU 72. DYNAMIC MODEL GUIDANCE IS IN AGREEMENT THAT TS 15W WILL TRACK NORTHWARD TO NORTH-NORTHEASTWARD THROUGH TAU 36 AND THEN TRACK NORTHWARD. DYNAMIC MODEL GUIDANCE HAS COME INTO SLIGHTLY BETTER AGREEMENT SINCE THE LAST MODEL RUN BUT OVERALL AGREEMENT REMAINS POOR. NAVGEM IS AN OUTLIER TO THE WEST BY TAU 72. ADDITIONALLY, GFS AND THE GFS ENSEMBLE STILL INDICATE A SLOWER TRACK SPEED. THE MODEL SPREAD BY TAU 72 IS 200 NM. THE JTWC FORECAST TRACK IS PLACED NEAR THE MULTI-MODEL CONSENSUS WITH LOW CONFIDENCE. C. IN THE LONG TERM, TS 15W WILL CONTINUE TO TRACK NORTHWARD WHILE POSITIONED ALONG THE WESTERN EDGE OF THE STR. AN APPROACHING WEST TO EAST MOVING SHORTWAVE TROUGH WILL HELP TO ACCELERATE TS 15W NORTHWARD. AS TS 15W TRACKS NORTHWARD IT WILL BEGIN EXTRATROPICAL TRANSITION (ETT) BY TAU 96 AND COMPLETE ETT BY TAU 120. DYNAMIC MODEL GUIDANCE HAS BOTH A LARGE ALONG-TRACK AND CROSS-TRACK DISAGREEMENT WITH A SPREAD OF 400 NM. THE JTWC FORECAST TRACK IS PLACED SLIGHTLY TO THE WEST OF THE MULTI-MODEL CONSENSUS WITH LOW CONFIDENCE.// NNNN NNNN