MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1244 AM EDT SUN JUN 14 2015 VALID JUN 14/0000 UTC THRU JUN 17/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z NAM/GFS EVALUATION WITH PRELIMINARY PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. UPPER LOW NEAR COASTAL BRITISH COLUMBIA TUE-WED ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: CLOSE TO THE 12Z ECMWF CONFIDENCE: BELOW AVERAGE ENSEMBLE SPREAD AND RUN TO RUN CONTINUITY IS POOR FOR THIS SYSTEM...AND THE LEADING EDGE OF MID-LEVEL HEIGHT FALLS IN THE FASTER 12Z UKMET IS SUPPORTED BY THE 12Z ECMWF MEAN. THE 00Z NAM/GFS ARE ON THE SLOWER SIDE TO BRING THE CLOSED LOW TOWARD THE SOUTHWEST COAST OF BRITISH COLUMBIA BUT ENSEMBLE CLUSTERING EDGED IN THE DIRECTION OF THE NAM/GFS WITH THE 12Z/13 CYCLE...VALID 12Z/17. AT THIS TIME...THE CENTER OF THE CLOSED LOW IN THE 12Z ECMWF IS SUPPORTED BEST BY ALL OF THE ENSEMBLES AND THE 12Z ECMWF IS IN THE MIDDLE OF THE LATEST ENSEMBLE SPREAD. WEAK STEERING CURRENTS MAKE FOR A DIFFICULT FORECAST TRACK OF THIS SYSTEM. LOW PRESSURE APPROACHING THE WRN GULF COAST MON NIGHT ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: 12Z CANADIAN/ECMWF COMPROMISE...00Z GFS A SECOND CHOICE CONFIDENCE: AVERAGE/SEE NHC OUTLOOKS THE PAST 3 CYCLES OF ECMWF/GEFS/CMC ENSEMBLE SCATTER LOW PLOTS HAVE SHOW REASONABLE AGREEMENT IN PLACEMENT...BUT HAVE BEEN JUMPING AROUND FROM RUN TO RUN. HOWEVER...THE 12Z/13 CYCLE SHOWS THE BEST CLUSTERING SO FAR AND BY 12Z/16...THEY SHOW A LOW JUST OFF THE S-CNTRL TEXAS COAST. THIS POSITION IS CLOSEST TO THE 12Z ECMWF/CMC AND IN AGREEMENT WITH THE 17Z WPC CONFERENCE CALL WITH NHC FROM SATURDAY. THE 00Z GFS IS A SECOND MATCH...BUT THE GFS IS LOCATED A BIT WEST OF THE PREFERENCE. FOR THE LATEST INFORMATION ON THE SYSTEM, SEE NHC TROPICAL WEATHER OUTLOOKS. SLOW-MOVING SHORTWAVE CURRENTLY APPROACHING THE SRN/CNTRL PLAINS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: NON 12Z CMC COMPROMISE CONFIDENCE: ABOVE AVERAGE THE 12Z CMC STANDS OUT FROM THE REMAINING MODEL CONSENSUS WITH A DIFFERENT ORIENTATION TO THE WEAK UPPER TROUGH AXIS ACROSS THE PLAINS THROUGH TUE. COLD FRONT SINKING DOWN THE MID-ATLANTIC COAST THROUGH SUN ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE NO MAJOR MODEL DIFFERENCES WERE OBSERVED WITH THIS SYSTEM. LOW AMPLITUDE UPPER TROUGH CROSSING THE CA/OR COAST ON MON ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: 00Z NAM...00Z GFS...12Z ECMWF BLEND CONFIDENCE: AVERAGE THE 12Z UKMET/CMC STAND OUT FROM THE LATEST ENSEMBLE CONSENSUS WITH THE AMPLITUDE OF THIS WAVE AS IT REACHING THE CNTRL PLAINS TUE NIGHT. THE NAM/GFS/ECMWF SHOW GOOD AGREEMENT WITH EACH OTHER AND THE ENSEMBLE MEANS. COLD FRONT PROGRESSING THROUGH THE DAKOTAS AND GREAT LAKES REGION ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE NO MAJOR MODEL DIFFERENCES WERE OBSERVED WITH THIS SYSTEM. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... OTTO