MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 06W (DANAS) WARNING NR 13// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 06W (DANAS), LOCATED APPROXIMATELY 374 NM SOUTH-SOUTHWEST OF KUNSAN AB, KOREA, HAS TRACKED NORTHWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A BROAD, WELL-DEFINED LOW-LEVEL CIRCULATION (LLC) WITH DEEP CONVECTIVE BANDING CONFINED, PRIMARILY, TO THE EASTERN SEMICIRCLE. A 190425Z AMSR2 89GHZ MICROWAVE IMAGE INDICATES IMPROVED BANDING WITH DEEP CONVECTIVE BANDING OVER THE EASTERN SEMICIRCLE WRAPPING INTO THE NORTH QUADRANT OF THE LLC SUGGESTING A SLIGHT INTENSIFICATION TREND. ADDITIONALLY, A LINE OF EXTENSIVE DEEP CONVECTION IS EVIDENT ALONG THE EASTERN AND NORTHEASTERN FLANK OF THE SYSTEM, AND, BASED ON RECENT KMA RADAR IMAGERY, IS EXPANDING ACROSS CHEJU ISLAND INTO THE SOUTHERN KOREAN PENINSULA. BASED ON THE IMPROVED STRUCTURE AND A SATCON ESTIMATE OF 53 KNOTS, THE INITIAL INTENSITY IS ASSESSED AT 45 KNOTS. OVERALL, THERE IS GOOD CONFIDENCE IN THE INITIAL POSITION BASED ON THE MSI. THE WIND FIELD REMAINS ASYMMETRIC AND EXPANSIVE WITH CONVERGENT GALE-FORCE WINDS FUELING THE PERSISTENT HEAVY CONVECTION OVER THE EASTERN SEMICIRCLE. THE WIND RADII FORECAST IS BASED ON THE MULTI-MODEL WIND RADII CONSENSUS (RVCN) AND REFLECTS THE EXTENSIVE SOUTHERLY GALE-FORCE WINDS. TS 06W IS TRACKING NORTHWARD ALONG THE WESTERN PERIPHERY OF A NORTH-SOUTH ORIENTED SUBTROPICAL RIDGE (STR) ENTRENCHED TO THE EAST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 06W IS FORECAST TO TRACK NORTH-NORTHEASTWARD TO NORTHEASTWARD AS IT ROUNDS THE NORTHWEST PERIPHERY OF THE STR. NUMERICAL MODEL GUIDANCE REMAINS IN GOOD AGREEMENT WITH A SPREAD OF 80NM AT TAU 36, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK ALTHOUGH THERE IS STILL SOME UNCERTAINTY IN THE EXACT LANDFALL LOCATION DUE TO THE BROAD NATURE OF THE CENTER. AS TS 06W APPROACHES THE SOUTHWEST COAST OF SOUTH KOREA NEAR TAU 24, IT IS FORECAST TO WEAKEN DUE TO FRICTIONAL EFFECTS WITH SIGNIFICANT WEAKENING FORECAST AFTER TAU 24 AS IT TRACKS ACROSS MOUNTAINOUS TERRAIN. THE SYSTEM SHOULD DISSIPATE COMPLETELY BY TAU 48.// NNNN NNNN