MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 135 AM EST WED NOV 18 2015 VALID NOV 18/0000 UTC THRU NOV 21/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION WITH PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GFS/NAM INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. DEEP CYCLONE APPROACHING THE PACIFIC NORTHWEST FRI NIGHT ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/UKMET/CANADIAN COMPROMISE CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE 00Z GFS BECOMES THE MOST SOUTHWEST WITH THIS OVERALL FEATURE, WHILE THE 00Z NAM IS ABNORMALLY WEAK. THE 12Z GLOBAL ENSEMBLE LOW CLUSTERING SUPPORTS A COMPROMISE OF THE 00Z ECMWF/00Z UKMET/00Z CANADIAN SOLUTION. THIS CHOICE IS PREFERRED WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE. SURFACE LOW APPROACHING THE PACIFIC NORTHWEST THU MORNING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: MODEL CONSENSUS CONFIDENCE: ABOVE AVERAGE THE GUIDANCE SHOWS GOOD AGREEMENT HERE. SHORTWAVE/LOW IN THE MIDWEST SATURDAY MORNING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/CANADIAN/UKMET COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 00Z NAM IS STRONGER ALOFT WITH THIS SYSTEM, WHICH LEADS TO A MUCH MORE NORTHERLY SURFACE SOLUTION. THE 12Z GLOBAL ENSEMBLE LOW CLUSTERING SUPPORTS A COMPROMISE OF THE 00Z ECMWF/00Z UKMET/00Z CANADIAN SOLUTION, WHICH IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE. THIS WILL ALSO HELP TAKE SOME OF THE EDGE OFF THE ECMWF'S STRONGER 700 HPA SOLUTION. CYCLONE MOVING THROUGH THE PLAINS TODAY/WED RESULTANT MERGED CYCLONE MOVING ACROSS ONTARIO FRONT PUSHING THROUGH THE EAST THU/FRI MORNING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/UKMET COMPROMISE CONFIDENCE: AVERAGE ALOFT, THE 00Z GFS REMAINS MORE EASTWARD WITH THE COMBINED MID-LEVEL SYSTEM, WHICH KEEPS ITS FRONTAL TIMING QUICKER THAN THE OTHER GUIDANCE. THE 12Z GLOBAL ENSEMBLE LOWS SUPPORT A BLEND OF THE 00Z ECMWF/00Z UKMET GUIDANCE WITH THE FRONT MOVING THROUGH THE EAST AND THE SURFACE LOW EXPECTED TO BYPASS NEW ENGLAND, WHICH IS PREFERRED WITH AVERAGE CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH