MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 138 PM EST SUN FEB 14 2016 VALID FEB 14/1200 UTC THRU FEB 18/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z MODEL EVALUATION WITH PREFERENCES/CONFIDENCE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GFS/NAM INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. SYSTEM APPROACHING THE PACIFIC NORTHWEST ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ THE GUIDANCE SHOWS GOOD AGREEMENT HERE, SO PREFER A GENERAL MODEL COMPROMISE WITH ABOVE AVERAGE CONFIDENCE. SYSTEM CROSSING THE MID MS/OH VALLEYS MON/TUE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS/ECMWF COMPROMISE CONFIDENCE: BELOW AVERAGE THERE ARE SLIGHT DEPTH ISSUES WITH THIS SYSTEM ALOFT, WHICH HAVE LED TO LATITUDE ISSUES WITH THE SURFACE LOW TRACK. THE 12Z NAM IS OUTSIDE THE 00Z GLOBAL ENSEMBLE ENVELOPE, AND NOT CONSIDERED USEFUL. WHILE THE 12Z GFS CLUSTERS WELL WITH THE MEANS AND LIE BEST WITHIN THE ENSEMBLE LOW CLUSTERING, THE 12Z UKMET/12Z ECMWF HAVE SHIFTED TO THE SOUTHERN FRINGE. DAY-TO-DAY CONTINUITY WITH THIS FEATURE HAS NOT BEEN GOOD IN THE UKMET/ECMWF SOLUTIONS, MAKING THEIR SOLUTIONS UNPALATABLE. HOWEVER, TO ACCOUNT FOR THEIR SHIFT, A COMPROMISE OF THE 12Z GFS/12Z ECMWF IS PREFERRED WITH BELOW AVERAGE CONFIDENCE. SRN PLAINS/EAST COAST SYSTEM MONDAY & TUESDAY ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS/ECMWF/UKMET/CANADIAN COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 12Z NAM WAS QUITE STRONG ALOFT WITH THIS SYSTEM AND EVENTUALLY SLOW WITH ITS PROGRESSION, SIMILAR TO UKMET RUNS FROM SATURDAY AND FITTING ITS USUAL BIAS BEYOND 48 HOURS. THE REST OF THE GUIDANCE IS NOW IN VERY GOOD AGREEMENT. PREFER A COMPROMISE OF THE 12Z RUNS OF THE GFS/ECMWF/UKMET/CANADIAN WITH ABOVE AVERAGE CONFIDENCE. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH