MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 26W (MEARI) WARNING NR 13// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 26W (MEARI), LOCATED APPROXIMATELY 361 NM SOUTH OF IWO TO, JAPAN, HAS TRACKED NORTHEASTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS AN ASYMMETRIC CENTRAL DENSE OVERCAST (CDO) FEATURE WITH DEEP CONVECTIVE BANDING OVER THE SOUTHERN SEMI-CIRCLE OF THE LOW LEVEL CIRCULATION CENTER (LLCC). A 051857Z SSMIS 91GHZ IMAGE DEPICTS A SMALL MICROWAVE EYE FEATURE, HOWEVER, DEEP CONVECTION OVER THE NORTHEAST QUADRANT HAS ERODED WITH THE BULK OF THE DEEP CONVECTION PRIMARILY CONFINED TO THE SOUTHWEST QUADRANT. BASED ON THE SSMIS IMAGE, THERE IS HIGH CONFIDENCE IN THE CURRENT POSITION. THE CURRENT INTENSITY IS ASSESSED AT 85 KNOTS BASED ON DVORAK INTENSITY ESTIMATES RANGING FROM T4.5 TO T5.0 (77 TO 90 KNOTS). UPPER-LEVEL ANALYSIS INDICATES THAT THE ANTICYCLONE PRVIOUSLY POSITIONED OVER THE SYSTEM CENTER HAS SHIFTED JUST EAST OF THE CENTER, AND IS NOW HINDERING DEVELOPMENT DESPITE CONTINUED VIGOROUS POLEWARD OUTFLOW. TY 26W IS TRACKING NORTHEASTWARD ALONG THE WESTERN PERIPHERY OF THE DEEP-LAYERED SUBTROPICAL RIDGE (STR). 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY MEARI IS EXPECTED TO CONTINUE TRACKING NORTHEASTWARD TO NORTH-NORTHEASTWARD THROUGHOUT THE FORECAST PERIOD ALONG THE WESTERN PERIPHERY OF THE STEERING STR. TY 26W WILL STEADILY INTENSIFY DUE TO ENHANCED POLEWARD OUTFLOW THROUGH TAU 24, BUT SHOULD WEAKEN AFTERWARDS DUE TO INCREASING VWS ASSOCIATED WITH AN APPROACHING MIDLATITUDE TROUGH. NEAR TAU 24, TY MEARI WILL BEGIN EXTRA-TROPICAL TRANSITION (ETT) AS IT INTERACTS WITH THE BAROCLINIC ZONE AND EMBEDS UNDER THE MIDLATITUDE WESTERLY FLOW. VWS ASSOCIATED WITH THE STRONG WESTERLIES WILL BECOME INCREASINGLY UNFAVORABLE AS THE SYSTEM GAINS LATITUDE. RAPID WEAKENING OF THE CYCLONE IS EXPECTED TO OCCUR AFTER TAU 36. THE TYPHOON WILL GAIN FRONTAL CHARACTERISTICS AND COMPLETE ETT AS A STRONG COLD-CORE LOW BY TAU 48. DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN NNNN