MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 02W (WUTIP) WARNING NR 27// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUPER TYPHOON (STY) 02W (WUTIP), LOCATED APPROXIMATELY 297 NM WEST-NORTHWEST OF ANDERSEN AFB, GUAM, HAS TRACKED NORTH-NORTHWESTWARD AT 05 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY SHOWS THE SYSTEM HAS MAINTAINED A HIGHLY SYMMETRIC PROFILE WITH DEEP ANNULAR CONVECTIVE RINGS SURROUNDING A SHARPLY-OUTLINED 22NM EYE. THE INITIAL POSITION IS BASED WITH HIGH CONFIDENCE ON THE EYE FEATURE IN THE EIR LOOP AFTER A SLIGHT TILT ADJUSTMENT USING THE NEAR-SURFACE MICROWAVE EYE FEATURE IN THE 36GHZ 251633Z AMSR2 IMAGE. THE INITIAL INTENSITY OF 125 KNOTS IS ASSESSED FROM AGENCY AND OBJECTIVE DVORAK ESTIMATES RANGING FROM T6.1 TO T7.0. DESPITE THE MARGINALLY FAVORABLE SEA SURFACE TEMPERATURES (SSTS) OF 26 TO 27C AND LOW OCEAN HEAT CONTENT, THE SYSTEM HAS MAINTAINED EXCELLENT RADIAL OUTFLOW WITH A VERY STRONG POLEWARD BIAS. THIS, IN ADDITION TO LOW (05-10 KNOT) VERTICAL WIND SHEAR (VWS) HAVE SUSTAINED ITS STY INTENSITY. THE CYCLONE IS TRACKING UNDER THE DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE NORTHEAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THROUGH TAU 24, STY 02W IS FORECAST TO TRACK NORTHWESTWARD TO WEST-NORTHWESTWARD SLOWLY UNDER THE STEERING INFLUENCE OF THE STR TOWARD A BREAK ASSOCIATED WITH A SHORTWAVE TO THE NORTH THAT IS PROPAGATING EASTWARD. GRADUAL WEAKENING IS EXPECTED AS VWS BEGINS TO INCREASE (15-20 KNOTS) ALONG THE NORTHERN PERIPHERIES AND DRY AIR ENTRAINMENT COMMENCES, AS EVIDENCED IN THE CIMSS ANIMATED TOTAL PRECIPITABLE WATER IMAGERY. AFTER TAU 24, THE SHORTWAVE TROUGH IS FORECAST TO SHIFT NORTHEAST ALLOWING AN EXTENSION OF THE LOW- TO MID-LEVEL STR TO REBUILD TO THE NORTH. CONSEQUENTLY, STY WUTIP WILL TURN WESTWARD AND ACCELERATE. MORE SIGNIFICANT WEAKENING IS EXPECTED BY TAU 36 AS VWS FURTHER INCREASES (GREATER THAN 25 KNOTS) AND SSTS DECREASE TO 26C. NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT WITH SOME UNCERTAINTY IN THE TIMING OF THE TURN TO THE WEST LEADING TO FAIR CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST. C. AFTER TAU 72, STY WUTIP WILL CONTINUE ON A WEST-NORTHWESTWARD TRACK UNDER THE AFOREMENTIONED STR EXTENSION. INCREASING VWS (30-40 KTS) AND CONVERGENCE ASSOCIATED WITH INCREASING UPPER-LEVEL (200MB) WESTERLIES OVER THE SYSTEM AS WELL AS DRY AIR ENTRAINMENT ASSOCIATED WITH A NORTHEAST SURGE EVENT WILL RAPIDLY WEAKEN THE SYSTEM, LEADING TO DISSIPATION BY TAU 120. NUMERICAL MODELS DIVERGE SIGNIFICANTLY ALONG AND ACROSS TRACKS BY OVER 300NM, LEADING TO LOW CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN NNNN