WDPN31 PGTW 220900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 19W (SAUDEL) WARNING NR 014// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 19W (SAUDEL), LOCATED APPROXIMATELY 336 NM SOUTH- SOUTHEAST OF HONG KONG, HAS TRACKED NORTH-NORTHWESTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) AND ENHANCED INFRARED SATELLITE IMAGERY INDICATES A GENERAL WEAKENING OF THE CONVECTIVE CORD, WITH THE AREA OF DEEP CONVECTION BECOMING MORE LIMITED IN AREAL EXTENT AND CONFINED TO THE EASTERN SEMICIRCLE. A CIMSS SIX HOUR TEMPERATURE TREND ANALYSIS CONFIRMS THAT CLOUD TOP TEMPERATURES NEAR THE CORE HAVE WARMED MORE THAN FIVE DEGREES CELSIUS NEAR THE CORE. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE WELL DEFINED MICROWAVE EYE FEATURE IN A 220528Z AMSR2 36 GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY IS HELD STEADY AT 65 KNOTS WITH HIGH CONFIDENCE BASED ON MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T4.0 (65 KNOTS) FROM PGTW AND RJTD, AN ADVANCED DVORAK TECHNIQUE (ADT) ESTIMATE OF T3.9 (63 KNOTS) AND A SATELLITE CONSENSUS ESTIMATE OF 58 KNOTS. ENVIRONMENTAL ANALYSIS REVEALS THE SYSTEM LIES IN A FAVORABLE ENVIRONMENT WITH LOW (15-20 KNOTS) VWS, WARM (28-29 DEG C) SSTS AND GOOD DUAL CHANNEL OUTFLOW. TY 19W IS MOVING SLOWLY NORTHWARD IN IN A WEAK STEERING ENVIRONMENT IN THE COL REGION BETWEEN SUBTROPICAL RIDGES LOCATED BOTH EAST AND WEST OF THE SYSTEM AND THE PASSAGE OF A MID-LATITUDE MAJOR SHORTWAVE TROUGH PASSING TO THE NORTH. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. IN THE NEAR-TERM, THROUGH TAU 12, TY 19W IS FORECAST TO CONTINUE TO DRIFT SLOWLY NORTHWARD OR MEANDER SLIGHTLY UNDER A WEAK STEERING REGIME AS IT REMAINS TRAPPED IN THE AFOREMENTIONED COL REGION. BY TAU 24, THE MAJOR SHORTWAVE TROUGH WILL MOVE EAST AND LIFT NORTHWARD, ALLOWING FOR THE STR TO THE EAST TO BUILD AND EXTEND TO THE WEST AND DRIVE TY 19W ONTO A WESTWARD TRACK THROUGH TAU 72. INTENSITY IS FORECAST TO REMAIN STEADY THROUGH TAU 12 AS THE SYSTEM REMAINS QUASI- STATIONARY, DUE TO UPWELLING OF COOLER WATERS BELOW 27 DEG CELSIUS, LIMITING THE AVAILABLE ENERGY FOR INTENSIFICATION. HOWEVER, AFTER THE SYSTEM STARTS MOVING WEST, IT WILL MOVE OVER WARMER WATERS ONCE AGAIN, AND COMBINE WITH A FAVORABLE SHEAR ENVIRONMENT WILL INTENSIFY SLIGHTLY, PEAKING AT 70 KNOTS BY TAU 36. AFTER TAU 48, INCREASING VWS AND COOLING SSTS WILL COMBINE TO SLOWLY WEAKEN THE SYSTEM AS IT PASSES SOUTH OF HAINAN. NUMERICAL MODELS ARE IN GENERAL AGREEMENT ON THE OVERALL TRACK SCENARIO, THOUGH WITH THE EXCEPTION OF AFUM AND THE UKMET ENSEMBLE, THE MAJORITY DO NOT CAPTURE THE NEAR-TERM NORTHWARD TRACK MOTION. BUT WITH THE EXCEPTION OF THE TWO AFOREMENTIONED MODELS, ALL OTHER MEMBERS OF THE CONSENSUS ARE TIGHTLY PACKED ON THE WESTWARD TRACK AFTER TAU 24. DUE TO THE NEAR-TERM NORTHWARD TRACK, THE JTWC OFFICIAL FORECAST LIES ON THE NORTHERN EDGE OF THE GUIDANCE ENVELOPE THROUGH TAU 72 WITH FAIR CONFIDENCE. C. BEYOND TAU 72, TY SAUDEL WILL TRACK MORE WEST-SOUTHWESTWARD AS THE STR TO THE WEST ASSUMES THE DOMINATE STEERING ROLE. THE SYSTEM IS FORECAST TO MAKE LANDFALL NORTH OF HUE, VIETNAM BETWEEN TAUS 72 AND 96 BEFORE CONTINUING SOUTHWESTWARD ACROSS LAOS BEFORE DISSIPATING OVER EASTERN THAILAND BY TAU 120. MODEL GUIDANCE SHOWS SIGNIFICANTLY MORE UNCERTAINTY AFTER TAU 72, WITH THE ECMWF AND THE ENSEMBLE INDICATING A WEST-NORTHWEST TRACK AFTER TAU 72, AND THE GFS SOLUTION INDICATING A LOOP BACK TO THE EAST BY TAU 120. THE REMAINDER OF THE CONSENSUS MEMBERS AGREE ON THE GENERAL WEST-SOUTHWEST TRACK AFTER TAU 72 THOUGH LANDFALL, WITH SIGNIFICANT (UP TO 410 NM) ALONG AND CROSS-TRACK SPREAD BY TAU 120. DUE TO THE WIDELY DIVERGENT SOLUTIONS IN THE EXTENDED FORECAST TRACK GUIDANCE, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.// NNNN