MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 14W (FOURTEEN) WARNING NR 06// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 14W (FOURTEEN), LOCATED APPROXIMATELY 262 NM WEST-SOUTHWEST OF WAKE ISLAND, HAS TRACKED WESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE AND IS BASED ON A 030000Z HIMAWARI VISIBLE SATELLITE IMAGE, WHICH SHOWS THE EXPOSED LLCC. THE INITIAL INTENSITY OF 35 KNOTS IS BASED ON A DVORAK CURRENT INTENSITY (CI) ESTIMATE OF T2.5 (35 KNOTS) FROM PGTW. ENVIRONMENTAL ANALYSIS SHOWS TS 14W IS EXPERIENCING FAVORABLE TO MODERATE (15 TO 20 KNOT) VERTICAL WIND SHEAR. POLEWARD AND EQUATORWARD OUTFLOW CHANNELS REMAIN WEAK BUT HAVE IMPROVED SLIGHTLY. SEA SURFACE TEMPERATURES ARE FAVORABLE FOR ADDITIONAL DEVELOPMENT, NEAR 30 DEGREES CELSIUS. TS 14W IS TRACKING WESTWARD WHILE UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE (STR), LOCATED TO THE NORTHEAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THE AFOREMENTIONED STR WILL REMAIN THE PRIMARY STEERING FEATURE THROUGH TAU 72 AS TS 14W BEGINS TO TRACK WEST-NORTHWESTWARD. SEA SURFACE TEMPERATURES WILL REMAIN FAVORABLE ALONG THE TRACK. UPPER LEVEL OUTFLOW AND VERTICAL WIND SHEAR WILL GRADUALLY IMPROVE AND ALLOW TS 14W TO SLOWLY INCREASE IN INTENSITY, REACHING 65 KNOTS BY TAU 72. DYNAMIC MODEL GUIDANCE HAS DIVERGED SINCE THE PREVIOUS MODEL RUN, BOTH IN ALONG-TRACK SPEED AND CROSS-TRACK SPREAD. MODEL GUIDANCE NOW HAS A SPREAD OF 220 NM BY TAU 72. THEREFORE, THERE IS NOW LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK. C. BEYOND TAU 72, THE STR WILL SHIFT EASTWARD AND ALLOW TS 14W TO BEGIN TO TRACK MORE NORTHWESTWARD. FAVORABLE SEA SURFACE TEMPERATURES (30 DEGREES CELSIUS), FAVORABLE VERTICAL WIND SHEAR AND AN ENHANCED POLEWARD OUTFLOW CHANNEL WILL ALLOW TS 14W TO INCREASE TO AN INTENSITY OF 90 KNOTS BY TAU 120. DYNAMIC MODEL GUIDANCE REMAINS IN POOR AGREEMENT BY TAU 120 WITH A SPREAD OF 320 NM. NAVGEM IS THE NOTABLE OUTLIER AND RE-CURVES TS 14W SIGNIFICANTLY EARLIER THAN THE REST OF THE MODEL GUIDANCE. THE JTWC FORECAST TRACK REMAINS SLIGHTLY TO THE WEST OF THE MULTI-MODEL CONSENSUS, FAVORING THE ECMWF TRACK. OVERALL, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.// NNNN NNNN