MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1209 AM EDT FRI OCT 28 2016 VALID OCT 28/0000 UTC THRU OCT 31/1200 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. SYSTEM APPROACHING NORTHERN CA/SOUTHERN OR EARLY MONDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS/UKMET COMPROMISE CONFIDENCE: SLIGHTLY ABOVE AVERAGE A SLIGHT TIMING ISSUE IS NOTED WITH THIS SYSTEM, WITH THE 00Z NAM THE QUICKEST AND THE 12Z ECMWF THE SLOWEST. THE 12Z ECMWF/18Z GEFS MEAN SOLUTIONS ARE CLOSEST TO A COMPROMISE OF THE 00Z GFS/12Z UKMET, WHICH IS FAVORED WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE. SYSTEM APPROACHING THE NORTHWEST LATE SUNDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: NON-NAM COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 00Z NAM WAS A SOUTHERLY OUTLIER WITH THE LOW MOVING INTO THE REGION. WITH THE 12Z ECMWF/18Z GEFS MEANS FARTHER NORTH CLOSER TO THE CONSENSUS AND AN UPSTREAM KICKER MOVING IN QUICKLY FROM THE PACIFIC, FAVOR A COMPROMISE OF THE 12Z ECMWF/12Z UKMET/00Z GFS/12Z CANADIAN HERE WITH ABOVE AVERAGE CONFIDENCE. AS THE SYSTEM ALOFT MOVES IN THE NORTHERN PLAINS, A SIMILAR COMPROMISE WORKS OUT WELL WITH THE SURFACE LOW IN THE DAKOTAS. SYSTEM RETROGRADING TOWARDS THE TX/MX BORDER MONDAY SHORTWAVE MOVING BY NEW ENGLAND SUNDAY NIGHT SYSTEM MOVING BY NEW ENGLAND SATURDAY SYSTEM MOVING BY NEW ENGLAND FRIDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ THE GUIDANCE SHOWS VERY GOOD AGREEMENT WITH THESE SYSTEMS. A COMPROMISE OF THE AVAILABLE GUIDANCE IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH