MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 127 AM EST SAT NOV 14 2015 VALID NOV 14/0000 UTC THRU NOV 17/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION WITH PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. TROUGH SPLITTING ACROSS THE WEST UPPER LOW MOVING THROUGH THE FOUR CORNERS MONDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/UKMET BLEND CONFIDENCE: AVERAGE WHILE THE GUIDANCE HANDLES THE NORTHERN STREAM PORTION OF THIS SYSTEM WELL, THE SOUTHERN STREAM PORTION INCREASINGLY DIFFERENT FROM MONDAY NIGHT ONWARD. THE 00Z GFS IS THE QUICKEST, GETTING THERE THROUGH A BOUT OF CONVECTIVE FEEDBACK -- ONE OF ITS USUAL PROBLEMS. ITS SURFACE LOW IS NEARLY OUTSIDE THE 12Z GLOBAL ENSEMBLE SPREAD, SO PLACED MINIMAL WEIGHT IN ITS SOLUTION. WITH ENERGY STILL DIGGING AROUND THE WEST SIDE OF THIS SYSTEM, AND CONSIDERING THE DEGREE OF SEPARATION BETWEEN THE CLOSED LOW AND THE NORTHERN STREAM PORTION OF THE TROUGH, ONE WOULD NORMALLY FEEL A SLOWER SOLUTION IS MORE IDEAL, IN LINE WITH THE 00Z NAM/21Z SREF MEAN. HOWEVER, THE NON-NCEP GUIDANCE IS CONVERGING UPON A SOLUTION CLOSE TO THE 00Z ECMWF/00Z UKMET, WHICH IS CLOSE TO THE 00Z GEFS MEAN -- THIS IS PREFERRED WITH AVERAGE CONFIDENCE. WITHIN THE CONVECTIVE REGIME ACROSS PORTIONS OF THE SOUTHERN PLAINS/MISSISSIPPI VALLEY, THE MASS FIELD PREFERENCE MAY NOT MATCH THE QPF PREFERENCE -- SEE OUR QPFPFD/QUANTITATIVE PRECIPITATION FORECAST DISCUSSION FOR MORE DETAILS ON THE QPF CHOICES. NORTHEAST UPPER TROUGH MONDAY/TUESDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: AVERAGE CHANGES IN THE 00Z NON-NCEP GUIDANCE HAVE LED TO SMALLER DIFFERENCES WITH THIS FEATURE. A COMPROMISE OF THE CURRENT CONSENSUS IS PREFERRED WITH AVERAGE CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH