MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 33W (TEMBIN) WARNING NR 03// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 33W (TEMBIN), LOCATED APPROXIMATELY 297 NM NORTHWEST OF SONSOROL, HAS TRACKED WESTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS A CONSOLIDATING SYSTEM WITH SIGNIFICANT CIRRUS OUTFLOW OBSCURING POTENTIAL CONVECTIVE BANDING FEATURES AND THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON EXTRAPOLATION FROM A 210348Z 36GHZ AMSR2 MICROWAVE IMAGE SHOWING DEEP CONVECTION WRAPPING INTO A LLCC FROM THE WESTERN SEMI- CIRCLE. THE INITIAL INTENSITY OF 35 KNOTS IS HEDGED ON THE UPPER END OF MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES RANGING FROM T2.0 TO T2.5 (30-35 KNOTS) FROM PGTW AND RJTD RESPECTIVELY. ENVIRONMENTAL ANALYSIS REVEALS FAVORABLE CONDITIONS WITH LOW TO MODERATE (10-15 KNOT) VERTICAL WIND SHEAR (VWS) AND WARM (29 CELSIUS) SEA SURFACE TEMPERATURES. UPPER LEVEL ANALYSIS SHOWS THAT THE SYSTEM HAS EQUATORWARD OUTFLOW AND STRONG POLEWARD OUTFLOW. TS 33W IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL STEERING RIDGE (STR) LOCATED TO THE NORTHEAST. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY SINCE THE LAST PROGNOSTIC REASONING MESSAGE. B. TS TEMBIN WILL INITIALLY TRACK WESTWARD AS A SUBTROPICAL RIDGE LOCATED TO THE NORTHWEST BECOMES THE PRIMARY STEERING FEATURE. THE TRACK WILL EVENTUALLY SHIFT MORE NORTHWESTWARD AFTER TAU 48. THE SYSTEM WILL MAKE LANDFALL OVER NORTHEASTERN MINDANAO SHORTLY AFTER TAU 12 AND CROSS THE SOUTHERN PHILIPPINES, EXITING INTO THE SOUTH CHINA SEA PRIOR TO TAU 36. AS THE SYSTEM TRACKS OVER LAND, TERRAIN INTERACTION WILL NOT ONLY LIMIT INTENSIFICATION, BUT IT WILL CAUSE A BRIEF WEAKENING PERIOD. ONCE IN THE SOUTH CHINA SEA FAVORABLE CONDITIONS WILL ALLOW FOR STEADY INTENSIFICATION WITH THE SYSTEM REACHING TYPHOON STRENGTH AROUND TAU 60 AND EVENTUALLY PEAK AT 75 KNOTS AROUND TAU 72. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT LENDING HIGH CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST. C. AFTER TAU 72, TS 33W IS FORECAST TO CONTINUE TO TRACK WEST- NORTHWESTWARD AS THE STEERING STR WEAKENS. AS THE SYSTEM TRACKS OVER THE SOUTH CHINA SEA INCREASING VERTICAL WIND SHEAR WILL BEGIN TO GRADUALLY WEAKEN THE SYSTEM. TS TEMBIN IS FORECAST TO MAKE LANDFALL OVER SOUTHERN VIETNAM AFTER TAU 96. AFTER LANDFALL, TERRAIN INTERACTION WILL RAPIDLY WEAKEN THE SYSTEM. AVAILABLE DYNAMIC MODEL GUIDANCE BEGINS TO SPREAD AFTER TAU 72 LEADING TO A SIGNIFICANT SPREAD BY TAU 120. DUE TO THE SPREADING IN LATER TAUS, THERE IS LOW CONFIDENCE IN THE EXTENDED PORTION OF THE JTWC TRACK FORECAST.// NNNN NNNN