WDPN31 PGTW 270300 COR MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 03W (JELAWAT) WARNING NR 10 CORRECTED// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION 03W (JELAWAT), LOCATED APPROXIMATELY 84 NM NORTH OF KAYANGEL, HAS TRACKED WEST-NORTHWESTWARD AT 8 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) INDICATES THAT TD 03W HAS A FULLY EXPOSED LLCC AND HAS SLOWED SIGNIFICANTLY. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE EXPOSED LLCC. A 262306Z AMSU-B 89 GHZ MICROWAVE IMAGE SHOWED WEAK BANDING WRAPPING INTO THE LLCC AND ANOTHER FLARE OF DEEP CONVECTION BEGINNING TO DEVELOP JUST TO THE NORTHWEST OF THE LLCC. THE INITIAL INTENSITY OF 30 KNOTS IS BASED ON A CONSENSUS OF MULTI- AGENCY DVORAK ESTIMATES T2.0 (30 KNOTS) FROM ALL REPORTING AGENCIES, SUPPORTED BY AN AUTOMATED SUBJECTIVE DVORAK ESTIMATE OF T2.5 (35 KNOTS). ENVIRONMENTAL ANALYSIS SHOWS THE SYSTEM IS TAPPING INTO A RELATIVELY STRONG POLEWARD OUTFLOW CHANNEL WHICH IS OFFSETTING THE VWS, WHICH HAS WEAKENED OVER THE PAST SIX HOURS TO THE LIGHT TO MODERATE (15-20 KNOTS) RANGE. TD 03W IS TRACKING WEST-NORTHWESTWARD ALONG THE SOUTHWESTERN EXTENT OF A DEEP-LAYER STR ANCHORED TO THE NORTHEAST BUT WHILE THE SIX HOURLY MOTION IS 8 KNOTS, OVER THE PAST THREE HOURS THE SYSTEM HAS BECOME NEARLY QUASI-STATIONARY AS AN EXTENSION OF THE STR LOCATED TO THE NORTHEAST DEVELOPED ACROSS THE NORTH SIDE OF THE SYSTEM. 3. FORECAST REASONING. A. THIS FORECAST REPRESENTS A CHANGE IN THE OVERALL PHILOSOPHY, DISSIPATING THE SYSTEM OVER WATER VICE TRANSITIONING TO AN EXTRA- TROPICAL CYCLONE. B. IN THE NEAR TERM, TD 03W IS FORECAST TO SLOWLY DRIFT WEST- NORTHWEST AS THE EXTENSION OF THE STR REMAINS IN PLACE OVER THE NEXT 6 TO 12 HOURS. AFTER THIS POINT THE STR BEGINS TO WEAKEN AND MOVE EASTWARD, ALLOWING TC 03W TO RETURN TO ITS NORTH-NORTHWESTWARD TRACK, EXPECTING TO ROUND THE RIDGE AXIS NEAR TAU 36 THEN SLOWLY ACCELERATE NORTHEASTWARD. VWS IS EXPECTED TO REMAIN LOW TO MODERATE THROUGH THE NEXT 24 HOURS, WHILE POLEWARD OUTFLOW REMAINS RELATIVELY ROBUST, ALLOWING THE SYSTEM TO INTENSIFY THROUGH TAU 48, PEAKING AT 45 KNOTS. MODEL GUIDANCE IS IN GOOD AGREEMENT IN THE ACROSS TRACK DIMENSION THROUGH TAU 48, WITH ECMWF BEING THE LARGEST OUTLIER TO THE WEST AND COAMPS DEFINING THE EASTERN BOUNDARY. NONE OF THE AVAILABLE MODELS PICKED UP ON THE SLOW DOWN IN FORWARD SPEED AND SO THE FORECAST TRACK IS SIGNIFICANTLY SLOWER THAN THE GUIDANCE THROUGH TAU 48. IN LIGHT OF THE SIGNIFICANT ALONG TRACK UNCERTAINTY, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST. C. AS PREVIOUSLY MENTIONED, THE FORECAST AFTER TAU 72 REPRESENTS A CHANGE IN THE OVERALL FORECAST PHILOSOPHY. THE ALTERNATE DISSIPATION SCENARIO DISCUSSED IN THE PREVIOUS DISCUSSION IS NOW FORECAST TO BE THE PRIMARY SCENARIO. DUE TO THE SLOW DOWN IN FORWARD MOTION, THE SYSTEM WILL NOT BE ABLE TO ROUND THE RIDGE FAST ENOUGH TO GET AHEAD OF A STRONG MID-LATITUDE HIGH PRESSURE SYSTEM MOVING ACROSS JAPAN BEGINNING AROUND TAU 72. THE MOVEMENT OF THIS HIGH INTO A POSITION DUE NORTH OF TD 03W BY TAU 96 WILL EFFECTIVELY BLOCK FURTHER NORTHWARD PROGRESSION BEYOND TAU 120. AFTER TAU 72, VWS WILL INCREASE DRAMATICALLY AS THE SYSTEM BEGINS TO INTERACT WITH THE MID- LATITUDE WESTERLY FLOW, DECOUPLING THE LLCC FROM THE UPPER-LEVEL ENERGY. AVAILABLE MODEL GUIDANCE IS STILL SPLIT AFTER TAU 72, BUT INCREASING NUMBER OF MEMBERS ARE TRENDING TOWARDS THE DISSIPATION SCENARIO, WITH NAVGEM AND HWRF NOW THE ONLY REMAINING MODELS SHOWING THE ETT SCENARIO. IN LIGHT OF THE SIGNIFICANT VARIATIONS IN THE MODEL GUIDANCE AND THE CHANGE IN FORECAST PHILOSOPHY, THERE IS LOW CONFIDENCE IN THE LONG RANGE JTWC TRACK FORECAST. 4. JUSTIFICATION FOR CORRECTION: CORRECTED MINOR TYPOGRAPHICAL ERRORS IN PARA 3.B. AND PARA 3.C.// NNNN