MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 154 PM EST TUE JAN 05 2016 VALID JAN 05/1200 UTC THRU JAN 09/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z MODEL EVALUATION WITH PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. SYSTEM MOVING THROUGH THE WEST THURSDAY/FRIDAY BOUNDARY IN THE SOUTHERN PLAINS/TX FRIDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS/ECMWF COMPROMISE CONFIDENCE: AVERAGE THE 12Z NAM/12Z UKMET SHOW A MORE PHASED SYSTEM BETWEEN THE NORTHERN PLAINS AND SOUTHERN ROCKIES/SOUTHERN PLAINS THAN THE OTHER GUIDANCE. THE GUIDANCE CAN HAVE A BIAS TOWARDS BEING TOO PHASED WITH SYSTEMS. WHILE THE 12Z CANADIAN FORMS A CONSENSUS ALOFT WITH THE 12Z GFS/12Z ECMWF, IT IS MORE SOUTHERLY WITH THE BOUNDARY IN TX, WHICH IS ONE OF ITS USUAL BIASES. PREFER THE SLOWER/LESS PHASED 12Z GFS/12Z ECMWF WITH THIS SYSTEM WITH AVERAGE CONFIDENCE. SHORTWAVE APPROACHING THE CENTRAL US/CAN BORDER FRI ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS/ECMWF COMPROMISE CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE 12Z UKMET IS THE QUICKEST WITH THIS SYSTEM'S PROGRESSION, WHILE THE 12Z ECMWF IS THE SLOWEST. THE PATTERN IN WHICH THE SYSTEM IS EMBEDDED (AN OMEGA-TYPE BLOCK) SUPPORTS A SLOWER SOLUTION THAN THE CURRENT NON-ECMWF CONSENSUS. THE 00Z ECMWF/12Z GEFS MEAN SOLUTIONS ARGUE FOR AN INTERMEDIATE SOLUTION, CLOSEST TO A COMPROMISE OF THE 12Z ECMWF/12Z GFS, WHICH IS PREFERRED WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE. SHORTWAVE MOVING THROUGH THE SOUTHWEST WEDNESDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: ECMWF/GFS/CANADIAN COMPROMISE CONFIDENCE: SLIGHTLY BELOW AVERAGE THE GUIDANCE IS IN BETTER AGREEMENT WITH THIS SYSTEM, AS THE 12Z CANADIAN/12Z ECMWF TRENDED TOWARDS A SOLUTION MORE RESEMBLING THE 12Z GFS. A COMPROMISE OF THE THREE IS PREFERRED WITH SLIGHTLY BELOW AVERAGE CONFIDENCE, AS THE PATTERN THE SYSTEM IS EMBEDDED WITHIN SUPPORTS A WEAKER SYSTEM THAN THE CURRENT CONSENSUS. SHORTWAVE SHEARING OUT ACROSS THE MIDWEST WEDNESDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ THE GUIDANCE SHOWS GOOD AGREEMENT WITH THIS SYSTEM, SO A BLEND OF THE AVAILABLE GUIDANCE IS PREFERRED WITH HIGH CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH