MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 230 AM EDT TUE APR 05 2016 VALID APR 05/0000 UTC THRU APR 08/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION WITH PREFERENCES/CONFIDENCE LEVELS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. CLIPPER HEADING THROUGH THE UPPER MS VALLEY THU NEGATIVELY TILTED UPPER TROUGH PIVOTING INTO CA THU NIGHT LOW WELL OFFSHORE CA THU NIGHT INTO FRIDAY MORNING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ THE GUIDANCE SHOWS REASONABLY GOOD AGREEMENT WITH THESE SYSTEMS, SO A GENERAL MODEL COMPROMISE IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE. TROUGH DIGGING ACROSS THE EAST CYCLONE HEADING FOR MI WED/NEW ENGLAND THU ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/UKMET/CANADIAN COMPROMISE CLOSE TO THE ECMWF CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE 00Z NAM IS SLOW TO MOVE THIS SYSTEM THROUGH NEW ENGLAND WHILE THE 00Z GFS NOW APPEARS TO BE OFF TO THE RACES WITH THIS SYSTEM, WITHIN THE NORTHEAST SIDE OF THE 12Z GLOBAL ENSEMBLE ENVELOPE. THE GUIDANCE IS IN RATHER GOOD AGREEMENT WITH THE DISSIPATION OF THE ORIGINAL CYCLONE IN THE LOWER GREAT LAKES AND COASTAL REDEVELOPMENT NEAR THE MID-ATLANTIC FALL LINE THURSDAY BEFORE IT ACCELERATES INTO THE ST. LAWRENCE VALLEY FRIDAY MORNING. TO DEAL WITH LINGERING DETAIL ISSUES WITH SYSTEM DEPTH ALOFT AND SURFACE LOW TRACK DIFFERENCES ACROSS NEW ENGLAND, A COMPROMISE OF THE WELL-CLUSTERED 00Z CANADIAN/00Z ECMWF/00Z UKMET APPEARS BEST -- WHICH ENDS UP CLOSE TO THE 00Z ECMWF -- PREFERRED WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH