WDPN33 PGTW 280300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 11W (NEPARTAK) WARNING NR 019// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 39.1N 141.6E INITIAL INTENSITY: 30 KTS GEOGRAPHIC REFERENCE: 80 NM SOUTH-SOUTHEAST OF MISAWA, JAPAN MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 13 KTS SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY, SYNOPTIC DATA, AND FIXES FROM RJTD AND PGTW INDICATE THAT TROPICAL DEPRESSION 11W (NEPARTAK) CAME ASHORE OVER MIYAGI PREFECTURE AT APPROXIAMTELY 272300Z, NEAR THE TOWN OF MINAMISANRIKU. THE CURRENT POSITION SPLITS THE FIXES FROM PGTW AND RJTD FIXES AND IS NORTH OF A LINE OF RADAR FIXES FROM THE JMA. THE CLOUD FIELDS SURROUNDING THE CORE EXPANDED AND BECAME LESS ORGANIZED AS THE SYSTEM TRACKED INLAND, MAKING POSITIONING LESS PRECISE THAN DESIRED. IMAGERY ALSO SHOWS THE SYSTEM ACCELERATING AND TAKING A MORE POLEWARD TRACK OVER THE PAST 12 HOURS. THE INTENSITY ASSESSMENT IS BASED ON A SLIGHT DROP AFTER THE SYSTEM MADE LANDFALL AT 35 KNOTS AND AGREES WITH THE RJTD DVORAK ESTIMATE OF 30KTS. SURFACE REPORTS DO NOT REFLECT ANY DESTRUCTIVE WINDS. SOME DEEP CONVECTION PERSISTS OVER THE NORTHERN SEMICIRCLE BUT THE MOST RECENT FRAMES INDICATE THAT THE HEAVIEST CONVECTIVE CLOUDS ARE COLLAPSING. INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND RADII). CURRENT STEERING MECHANISM: A HIGH AMPLITUDE RIDGE EXTENDING NORTHWESTWARD FROM THE SUBTROPICAL HIGH EXTENDS OVER THE SOUTHERN KURILS, FORCING THE SYSTEM TOWARDS THE SEA OF JAPAN. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: NO CURRENT ESTIMATE RJTD: T2.0 - 30 KTS FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE VWS: 0-5 KTS SST: OVER LAND OUTFLOW: WEAK RADIAL ANALYSIS CONFIDENCE: INITIAL POSITION: LOW INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: NOT APPLICABLE 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TROPICAL DEPRESSION 11W (NEPARTAK) HAS MADE LANDFALL AND IS NOW HEADING ACROSS NORTHERN HONSHU TOWARDS THE SEA OF JAPAN. THE LOW LEVEL CIRCULATION CETNER (LLCC) REMAINS VERTICALLY STACKED WITH AN UPPER LEVEL CYCLONE AND IS MOVING IN TANDEM TOWARDS THE SEA OF JAPAN. AMSU RADIAL HEIGHT CROSS SECTIONS CONTINUE TO SUPPORT THE ASSESSMENT THAT TROPICAL DEPRESSION 11W IS A SUB-TROPICAL SYSTEM. THE SUBTROPICAL HIGH IS ANCHORED NEAR 39N 170E. THERE IS AN EXPANSIVE LOW-TO-MID-LEVEL RIDGE EXTENDING FROM THE SYSTEM CENTER ACROSS THE SOUTHERN KURILS THAT IS EXPECTED TO FORCE THE SYSTEM WESTWARD INTO THE SEA OF JAPAN. WHETHER OR NOT THE LOW LEVEL CIRCULATION CENTER SURVIVES THE TRIP OVER THE ROUGH TERRAIN OF THE JAPANESE ALPS REMAINS UNCERTAIN, BUT A NUMBER OF VORTEX TRACKERS AND ENSEMBLE MEMBERS CARRY THE SYSTEM INTO THE SEA OF JAPAN (SOJ). THE FARTHER NORTH THE LLCC EMERGES, THE MORE QUICKLY IT WILL DISSIPATE OVER WATER. SEA SURFACE TEMPERATURES FALL PRECIPITOUSLY NORTH OF THE 40TH LATITUDE AND WILL NOT SUPPORT THE SYSTEM. NO MATTER WHERE THE VORTEX EMERGES INTO THE SOJ, IT WILL ENCOUNTER GREATER THAN 25 KNOTS OF VERTICAL WIND SHEAR. MODEL DISCUSSION: THE JTWC TRACK FORECAST STAYS CLOSE TO CONSENSUS WHILE THE INTENSITY FORECAST DROPS THE INTENSITY QUICKER THAN GUIDANCE DUE TO EXPECTED DECAY ON THE OVERLAND TRACK. SOME MODELS AND ENSEMBLE MEMBERS SHOW THE VORTEX SURVIVING INTO THE SOJ THROUGH TAU 48, BUT DUE TO THE COOLER WATERS AND HIGH VERTICAL WINDSHEAR, EVEN IF THE LLCC PERSISTS IT WILL NOT BE ABLE TO RE-GENERATE TO OVER 20 KNOTS. FORECAST CONFIDENCE: TRACK 0 - 72 HR: LOW INTENSITY 0 - 72 HR: MEDIUM// NNNN