WDPN31 PGTW 251500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 27W (WUKONG) WARNING NR 04// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION (TD) 27W (WUKONG), LOCATED APPROXIMATELY 370 NM SOUTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY ALONG WITH A 251126Z SSMIS 91GZ MICROWAVE IMAGE SHOWS TD 27W CONTINUES TO DISPLAY A PARTIALLY EXPOSED LOW-LEVEL CIRCULATION CENTER WITH LIMITED DEEP CENTRAL CONVECTION AND A LARGE CONVERGENT BAND OVER THE NORTHWEST QUADRANT. DVORAK INTENSITY ESTIMATES HAVE REMAINED AT 30 KNOTS FROM BOTH PGTW AND KNES AND THE INITIAL INTENSITY REMAINS ASSESSED AT 30 KNOTS BASED ON THESE DVORAK ESTIMATES AS WELL AS THE CURRENT STRUCTURE OF THE SYSTEM. UPPER LEVEL ANALYSIS AS WELL AS ANIMATED WATER VAPOR IMAGERY REVEALS POLEWARD OUTFLOW REMAINS ROBUST BUT IS BEING OFFSET BY MODERATE (10- 20 KNOTS) VERTICAL WIND SHEAR. TD 27W IS TRACKING WEST-NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF THE DEEP SUBTROPICAL RIDGE (STR) ENTRENCHED OVER THE WESTERN NORTH PACIFIC OCEAN. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TD 27W IS FORECAST TO CONTINUE TRACKING WEST-NORTHWESTWARD THROUGH TAU 48 AS IT TRACKS TOWARD THE WESTERN EXTENT OF THE STR. THE SYSTEM IS EXPECTED TO REMAIN AT ITS CURRENT INTENSITY AS IT TRACKS ACROSS THE CENTRAL PHILIPPINE ISLANDS FOR THE NEXT 12 HOURS AND THEN INTENSIFY AS IT REEMERGES IN THE NORTHERN SULU SEA AND INTO THE SOUTH CHINA SEA. VERTICAL WIND SHEAR WILL INCREASE AFTER TAU 48 AHEAD OF A MID-LATITUDE TROUGH WHICH WILL FURTHER WEAKEN THE SYSTEM. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT AND THE JTWC FORECAST IS POSITIONED CLOSE TO THE MULTI-MODEL CONSENSUS WITH A MINOR ADJUSTMENT TO OFFSET WBAR, WHICH CONTINUES TO RECURVE TD 27W NORTHWARD THROUGH THE STR. C. IN THE EXTENDED TAUS, TD 27W IS FORECAST TO WEAKEN DUE TO THE FURTHER INCREASING VERTICAL WIND SHEAR ASSOCIATED WITH A FORECASTED NORTHEASTERLY SURGE EXPECTED OVER THE SOUTH CHINA SEA. AS THE SYSTEM WEAKENS, IT WILL TURN WEST-SOUTHWESTWARD TO SOUTHWESTWARD UNDER THE STEERING INFLUENCE OF THE LOW-LEVEL NORTHEASTERLY FLOW AND DISSIPATE BY TAU 96. OVERALL, HIGH CONFIDENCE REMAINS IN THE JTWC FORECAST.// NNNN