MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 239 PM EDT FRI JUN 12 2015 VALID JUN 12/1200 UTC THRU JUN 16/0000 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. POSSIBLE CONVECTIVE LOW IN THE GULF MON/TUE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: WEAK VERSION OF THE NON-UKMET GUIDANCE CONFIDENCE: BELOW AVERAGE THE NON-UKMET GUIDANCE FORMS A CONVECTIVE LOW EAST OF BELIZE SATURDAY NIGHT WHICH CROSSES THE YUCATAN PENINSULA AND MOVES INTO THE WESTERN GULF OF MEXICO MONDAY NIGHT. NOW THAT THE 12Z ECMWF HAS JOINED THE CLUB, THERE IS HIGHER CONFIDENCE OF SUCH AN OCCURRENCE. THE 17Z CONFERENCE CALL WITH NHC TODAY LED TO A SURFACE TROUGH WITH ROUGHLY THE TIMING OF THE 12Z GFS/12Z CANADIAN/12Z ECMWF/12Z NAM. A WEAK VERSION OF THIS CONSENSUS IS PREFERRED WITH BELOW AVERAGE CONFIDENCE DUE TO POOR RUN-TO-RUN AND DAY-TO-DAY CONTINUITY OF THE NON-CANADIAN GUIDANCE. SHORTWAVE LIFTING INTO THE MIDWEST SUN NIGHT ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: NON-NAM COMPROMISE CONFIDENCE: ABOVE AVERAGE AT 700 HPA, THE 12Z NAM APPEARS TO BE A DEEP OUTLIER WITH THIS SYSTEM -- ITS USUAL BIAS. PREFER A NON-NAM SOLUTION HERE WITH ABOVE AVERAGE CONFIDENCE. ELSEWHERE ~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE WITH THE OTHER SYSTEMS NEAR THE LOWER 48, THE MODEL GUIDANCE SHOWS GOOD AGREEMENT MASS FIELD-WISE. PREFER A GENERAL MODEL COMPROMISE WITH ABOVE AVERAGE CONFIDENCE. FOR QPF THOUGHTS, SEE OUR QUANTITATIVE PRECIPITATION FORECAST DISCUSSION (NFDQPFPFD IN AWIPS2) FOR MORE INFORMATION. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ROTH