MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1208 AM EDT FRI OCT 09 2015 VALID OCT 09/0000 UTC THRU OCT 12/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z GFS/NAM EVALUATION WITH PRELIMINARY MODEL PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. SYSTEM NEAR THE SOUTHEAST SAT INTO MON ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GFS/ECMWF/UKMET COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 12Z CANADIAN TAKES A PORTION OF THIS SYSTEM ALONG THE GULF STREAM TO THE NORTHEAST BEFORE THE OTHER GUIDANCE, SEEMINGLY TREATING IT AS A TROPICAL CYCLONE. THE 00Z NAM SHOWS A SIMILAR ISSUE, THOUGH ITS SURFACE LOW MOVES OUT SLOWER AND IS WEAKER. OTHERWISE, DIFFERENCES ARE MINIMAL BETWEEN THE 00Z GFS/12Z ECMWF/12Z UKMET; A COMPROMISE OF THE THREE IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE. SYSTEMS MOVING BY WESTERN CANADA FRI/SAT UPPER LOW DROPPING THROUGH NORTHWEST MEXICO SYSTEM MOVING THROUGH THE NORTHEAST LATE FRIDAY SYSTEM MOVING NEAR THE US/CANADIAN BORDER LATE SAT-MON AM ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE THE GUIDANCE IS IN GOOD AGREEMENT WITH THESE SYSTEMS. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH