MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 14W (FOURTEEN) WARNING NR 05// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 14W (FOURTEEN), LOCATED APPROXIMATELY 207 NM SOUTHWEST OF WAKE ISLAND, HAS TRACKED WEST-NORTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY SHOWS A POCKET OF DEEP CONVECTION WHICH IS OFFSET TO THE EAST OF THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE AND IS BASED ON A 021821Z GMI 89GHZ MICROWAVE IMAGE WHICH SHOWS EXCELLENT LOW LEVEL BANDING AND DEEP CONVECTION SHEARED TO THE EAST OF THE 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 NEUTRAL (15 TO 20 KNOT) VERTICAL WIND SHEAR. POLEWARD AND EQUATORWARD OUTFLOW CHANNELS REMAIN WEAK. SEA SURFACE TEMPERATURES ARE FAVORABLE FOR ADDITIONAL DEVELOPMENT, NEAR 30 DEGREES CELSIUS. TS 14W IS TRACKING WEST-NORTHWESTWARD WHILE UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE (STR), LOCATED TO THE NORTHEAST. 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 TRACKS WEST-NORTHWESTWARD. SEA SURFACE TEMPERATURES WILL REMAIN FAVORABLE ALONG THE FORECAST TRACK. HOWEVER, MARGINAL VERTICAL WIND SHEAR AND LIMITED UPPER LEVEL OUTFLOW CHANNELS WILL ALLOW TS 14W TO SLOWLY INCREASE IN INTENSITY, REACHING 60 KNOTS BY TAU 72. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT THAT TS 14W WILL TRACK GENERALLY WEST-NORTHWESTWARD TROUGH TAU 72. MODEL GUIDANCE HAS A SPREAD OF 113 NM BY TAU 72. THEREFORE, THERE IS HIGH 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 NORTHWARD. 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 IS IN POOR AGREEMENT BY TAU 120 WITH A SPREAD OF 415 NM. NAVGEM IS THE NOTABLE OUTLIER AND RE-CURVES TS 14W SIGNIFICANTLY EARLIER THAN THE REST OF THE MODEL GUIDANCE. THE JTWC FORECAST TRACK IS PLACED SLIGHTLY TO THE WEST OF THE MULTI-MODEL CONSENSUS. OVERALL, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK. // NNNN NNNN