MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 16W (MERANTI) WARNING NR 18// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUPER TYPHOON (STY) 16W (MERANTI), LOCATED APPROXIMATELY 398 NM SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS ANOTHER PHASE OF COOLING CLOUD TOPS DEPICTING STRENGTHENING WITHIN THE CORE OF THE CYCLONE SURROUNDING A DISTINCT 8NM EYE. THE EYE FEATURE SUPPORTS THE CURRENT POSITION WITH HIGH CONFIDENCE. THE INITIAL INTENSITY HAS BEEN INCREASED TO 160 KNOTS BASED ON THE COOLING CLOUD TOPS AND IS SUPPORTED BY A CONTINUOUS INCREASE IN SATCON INTENSITY ESTIMATES WHICH NOW STAND AT 164 KNOTS. DVORAK CURRENT INTENSITY ESTIMATES FROM PGTW AND RJTD REMAIN AT 155 KNOTS (T7.5). THE WATER VAPOR LOOP SHOWS RADIAL OUTFLOW DUE TO A POINT SOURCE ANTI-CYCLONE OVER THE TOP OF THE SYSTEM WITH LOW (5-10 KNOT) VERTICAL WIND SHEAR (VWS). SEA SURFACE TEMPERATURES NEAR 30 CELSIUS AND HIGH OCEAN HEAT CONTENT ARE ALSO VERY FAVORABLE. STY 16W CONTINUES TO TRACK TOWARD THE WEST- NORTHWEST UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR) TO THE NORTH. 3. FORECAST REASONING. A. NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THROUGH TAU 72, STY 16W WILL TRACK GENERALLY WEST- NORTHWESTWARD UNDER THE STEERING INFLUENCE OF THE STR. VERY FAVORABLE ENVIRONMENTAL CONDITIONS WILL ALLOW THE INTENSE CYCLONE TO MAINTAIN INTENSITY OVER THE NEXT 12 HOURS. AFTERWARDS, LAND INTERACTION WITH TAIWAN AND INCREASING VWS WILL BEGIN THE WEAKENING PHASE. STY MERANTI WILL MAKE LANDFALL ALONG THE COAST OF CHINA JUST NEAR TAU 48 AS A STRONG TYPHOON. DYNAMIC MODEL GUIDANCE HAS COME INTO MUCH BETTER AGREEMENT WITH A TRACK THAT PASSES JUST SOUTH OF TAIWAN. AT THIS TIME ONLY NAVGEM CLIPS THE SOUTHERN TIP OF TAIWAN. C. IN THE EXTENDED FORECAST, STY 16W WILL CONTINUE TRACKING OVER LAND AND FULLY DISSIPATE DUE TO LAND INTERACTION AND INCREASED VWS AS IT INTERACTS WITH THE ZONAL MID-LATITUDE WESTERLY FLOW. MODEL GUIDANCE IN THE EXTENDED FORECAST DIVERGES GREATLY DUE TO THE RAPID WEAKENING OF THE CYCLONE. VWS IS EXPECTED TO BE IN EXCESS OF 30 KNOTS AT THIS TIME. DUE TO THE IMPROVED MODEL AGREEMENT PRIOR TO LANDFALL AND THE STABILITY OF THE MULTI-MODEL CONSENSUS OVER THE PAST TWO CYCLES, THERE IS NOW HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN NNNN