MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1122 AM EST WED NOV 16 2016 VALID NOV 16/1200 UTC THRU NOV 20/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z NAM/GFS EVALUATION WITH PRELIMINARY MODEL PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. DEEP LAYER CYCLONE IN THE EASTERN PACIFIC ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/UKMET COMPROMISE CONFIDENCE: SLIGHTLY ABOVE AVERAGE ON FRIDAY NIGHT, THE GFS LOWERS MID-LEVEL HEIGHTS MORE THAN THE ECMWF, WHICH LEADS TO MORE INTRUSION OF ONSHORE FLOW/PRECIPITATION INTO THE NORTHWEST. EVENTUALLY, THE 12Z GFS IS MORE EASTWARD WITH THE DEEP LAYERED CYCLONE THAT THE OTHER GUIDANCE -- ITS USUAL BIAS. THE 00Z UKMET IS WEAKER WITH THE LEADING SHORTWAVE AND HANGS THE SYSTEM FARTHER BACK LIKE THE 00Z ECMWF, WHICH BETTER FITS THE 06Z GEFS/00Z ECMWF ENSEMBLE MEAN SOLUTIONS. PREFER A COMPROMISE OF THE 00Z ECMWF/00Z UKMET HERE WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE. SYSTEM MOVING FROM THE PLAINS THROUGH THE GREAT LAKES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS INTO FRIDAY MORNING GFS/ECMWF COMPROMISE THEREAFTER CONFIDENCE: SLIGHTLY ABOVE AVERAGE THERE ARE TIMING ISSUES IN THE GUIDANCE, WITH THE 00Z CANADIAN/00Z ECMWF ON THE SLOW SIDE AND THE 12Z NAM AND EVENTUALLY THE 12Z GFS THE QUICKEST. THE CANADIAN, ECMWF, AND GFS ARE FITTING THEIR USUAL BIASES, ARGUING ULTIMATELY FOR AN INTERMEDIATE SOLUTION. THE 00Z GLOBAL ENSEMBLE SPREAD SHOWS A FAMILIAR CLUSTERING -- ECMWF MEMBERS ARE SLOWER THAN THE GEFS MEMBERS, BUT THERE IS OVERLAP. THE 12Z GFS FITS THE OVERLAP ON THURSDAY AND FRIDAY BEFORE SHIFTING MORE INTO THE GEFS CAMP. ALOFT, THE ECMWF LOOKS WAY TOO WEAK WITH A SYSTEM UP IN HUDSON BAY, EVEN WHEN COMPARED TO ITS ENSEMBLE MEAN, ARGUING FOR A QUICKER SOLUTION. WHILE THE UKMET APPEARS TO SHOW AN INTERMEDIATE PROGRESSION, IT IS THE STRONGEST ALOFT WHICH IS BOUND TO BIAS ITS SURFACE AND PRECIPITATION PATTERNS. THE 12Z GFS IS PREFERRED INTO FRIDAY BEFORE SWITCHING TO A 12Z GFS/00Z ECMWF THEREAFTER. CONFIDENCE IN THIS SOLUTION IS SLIGHTLY ABOVE AVERAGE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH