MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 137 PM EST FRI NOV 14 2014 VALID NOV 14/1200 UTC THRU NOV 18/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z MODEL EVALUATION WITH PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT APPEAR TO DEGRADE ITS SHORT RANGE FORECASTS. SHORTWAVE MOVING ACROSS THE GREAT LAKES SUNDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: UKMET/ECMWF/CANADIAN COMPROMISE CONFIDENCE: AVERAGE THE 12Z GFS/12Z NAM ARE QUICKER THAN THE OTHER GUIDANCE WITH THIS SYSTEM -- FITTING THE USUAL BIAS OF THE GFS. THE 12Z UKMET/12Z ECMWF/12Z CANADIAN FIT THE 00Z ECMWF/06Z GEFS/TO SOME DEGREE THE 09Z SREF ENSEMBLE MEAN SOLUTIONS THE BEST. A COMPROMISE OF THE 12Z UKMET/12Z ECMWF/12Z CANADIAN ARE PREFERRED WITH THIS SYSTEM WITH AVERAGE CONFIDENCE CONSIDERING ITS QUICK PROGRESSION. UPPER TROUGH ENVELOPING MUCH OF THE UNITED STATES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/UKMET/CANADIAN COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 12Z NAM LAGS THE REMAINDER OF THE GUIDANCE WITH THE PROGRESSION OF THE MAIN UPPER TROUGH, WHILE THE 12Z GFS SPEED AHEAD -- BEFITTING THEIR KNOWN BIASES. THE 00Z ECMWF/06Z GEFS/09Z SREF ENSEMBLE MEANS BEST AGREE WITH THE 12Z CANADIAN/12Z UKMET/12Z ECMWF SOLUTIONS, WHICH ARE PREFERRED WITH ABOVE AVERAGE CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH