MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 18W (MALAKAS) WARNING NR 16// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON 18W (MALAKAS), LOCATED APPROXIMATELY 489 NM SOUTH OF KADENA AB, HAS TRACKED NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A WARMING PINHOLE EYE FEATURE THAT HAS RECENTLY EMERGED. THE INITIAL POSITION IS BASED ON SATELLITE FIXES FROM PGTW AND RJTD AS WELL AS A 151028Z SSMIS 91GHZ IMAGE WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 90 KNOTS AND IS BASED ON SUBJECTIVE DVORAK ESTIMATE FROM PGTW AND RJTD NOW REPORTING THE CURRENT INTENSITY AT T4.5 (90 KNOTS). UPPER-LEVEL ANALYSIS SHOWS IMPROVING POLEWARD OUTFLOW AND VERTICAL WIND SHEAR, HOWEVER THERE IS A DEEPENING UPPER-LEVEL LOW OFF TO THE EAST CREATING A REGION OF SUBSIDENCE AND CURRENTLY HAVING MINIMAL AFFECT ON THE SYSTEM. SEA SURFACE TEMPERATURES ARE VERY FAVORABLE NEAR 30 CELSIUS. CURRENTLY TY MALAKAS IS TRACKING WEST-NORTHWEST ALONG THE PERIPHERY OF A DEEP- LAYERED SUBTROPICAL RIDGE. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. IN THE NEAR TERM FORECAST TY MALAKAS WILL CONTINUE TO TRACK NORTHWEST ALONG THE STEERING RIDGE UNDER FAVORABLE CONDITIONS. THE UPPER-LEVEL LOW IS EXPECTED TO PERSIST AND MITIGATE OUTFLOW ON THE EASTERN PERIPHERY, HOWEVER ENHANCED POLEWARD FLOW IS ALSO EXPECTED TO IMPROVE PROVIDING A WINDOW FOR INTENSIFICATION THROUGH TAU 36 REACHING A PEAK INTENSITY OF 115 KNOTS. FROM TAU 36 TO 72, TY MALAKAS WILL BEGIN TO SLOW DOWN AS IT ROUNDS THE RIDGE AXIS NEAR NORTHEASTERN TAIWAN. SLIGHT LAND INTERACTION IS EXPECTED DURING THIS TIME LEADING TO A GRADUAL WEAKENING TREND. C. IN THE EXTENDED TAUS BEYOND TAU 72, TY MALAKAS WILL TRACK NORTHEASTWARD ALONG THE NORTHERN PERIPHERY OF THE SUBTROPICAL RIDGE INTO THE WESTERLY JET. VERTICAL WIND SHEAR WILL INCREASE SIGNIFICANTLY LEADING TO RAPID WEAKENING OF THE SYSTEM BY TAU 120. DYNAMIC MODEL GUIDANCE IS STILL SHOWING SOME UNCERTAINTY AS TY MALAKAS ROUNDS THE RIDGE AXIS, BUT OVERALL NUMERICAL SOLUTIONS ARE SHOWING TIGHTER GROUPING. THE DECREASED UNCERTAINTY LENDS HIGH CONFIDENCE TO THE FORECAST TRACK.// NNNN NNNN