MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1223 AM EDT FRI JUL 11 2014 VALID JUL 11/0000 UTC THRU JUL 14/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z GFS/NAM EVALUATION WITH PRELIMINARY MODEL PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GFS/NAM INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. DEEP CYCLONE ACROSS SOUTHEAST CANADA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: CANADIAN/ECMWF/GFS COMPROMISE CONFIDENCE: ABOVE AVERAGE AS RIDGING AMPLIFIES OVER THE SOUTHERN CANADIAN ROCKIES, A DOWNSTREAM COLD LOW IS EXPECTED TO DROP SOUTHWARD TOWARDS INTERNATIONAL FALLS, WITH A PIECE OF ENERGY ESCAPING NORTHEAST INTO QUEBEC. THE 00Z NAM IS THE FARTHEST WEST WITH THIS SYSTEM AND STRONGER WITH A LOW MOVING THROUGH MICHIGAN -- TWO OF ITS USUAL BIASES -- WHILE THE 12Z UKMET IS THE QUICKEST -- ONE OF ITS USUAL BIASES. CONSIDERING ABOVE, PREFER A COMPROMISE OF THE 12Z CANADIAN/12Z ECMWF/00Z GFS GUIDANCE WITH ABOVE AVERAGE CONFIDENCE CONSIDERING THE MODEL BIASES. SYSTEM MOVING INTO THE NORTHWEST SUNDAY/MONDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: NON-CANADIAN COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 12Z CANADIAN WAS SLOW WITH THIS SYSTEM -- ITS USUAL BIAS -- WHICH IS EMBEDDED WITHIN MODEST SOUTH-SOUTHWESTERLY FLOW. THE PREFERENCE IS FOR A NON-CANADIAN COMPROMISE WITH ABOVE AVERAGE CONFIDENCE CONSIDERING ITS KNOWN BIAS. UPPER LEVEL SHORTWAVE MOVING THROUGH NORTHERN MEXICO ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: BLEND OF THE OPERATIONAL MODELS CONFIDENCE: ABOVE AVERAGE THE GUIDANCE IS IN GOOD AGREEMENT WITH THIS SYSTEM. A GENERAL MODEL COMPROMISE IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE CONSIDERING THE MINIMAL MODEL SPREAD. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH