MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 232 AM EDT WED JUN 15 2016 VALID JUN 15/0000 UTC THRU JUN 18/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION WITH FINAL PREFERENCES AND FORECAST CONFIDENCE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ CLOSED LOW SLOWLY EXITING NEW ENGLAND THROUGH THU ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL BLEND CONFIDENCE: ABOVE AVERAGE THE 00Z NAM ENDS UP A BIT FASTER THAN THE CONSENSUS FRI AS THE SYSTEM REACHES NEWFOUNDLAND... AND THE 00Z GFS IS A TAD SLOWER. HOWEVER...THERE IS GENERALLY TIGHT CLUSTERING WITH THE GUIDANCE SOLUTIONS WITH THIS FEATURE...SO A GENERAL MODEL BLEND IS PREFERRED. SHORTWAVE TRACKING FROM THE NRN PLAINS TODAY TO THE MID-ATLANTIC FRI SURFACE LOW FORMING OVER THE MID ATLANTIC FRI AFTERNOON/EVENING ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: THROUGH 18/00Z 00Z GFS/00Z ECMWF/00Z UKMET BLEND AFTER 18/00Z...00Z GFS/00Z UKMET/00Z GEFS MEAN/12Z ECWMF ENSEMBLE MEAN CONFIDENCE: AVERAGE THE 00Z NAM AND GFS ARE CLOSE TO THE CONSENSUS AS THE SHORT WAVE TRACKS DOWN THE MID LEVEL RIDGE TO THE MID ATLANTIC COAST FRI. AFTER THAT TIME...THE 00Z NAM IS A BIT FASTER THAN THE CONSENSUS...WHILE THE 00Z GFS IS A BIT DEEPER AND MORE AMPLIFIED WITH THE DEVELOPING LONG WAVE TROUGH OVER THE SOUTHERN MID ATLANTIC/SOUTHEAST. IN GENERAL...THESE SOLUTIONS ARE CLOSE TO THE CONSENSUS INTO FRI NIGHT. THE 00Z NAM/00Z CMC ARE A BIT FASTER WITH THE SURFACE LOW FORMING ALONG THE THE NC COAST FRI. THERE IS BETTER AGREEMENT THROUGH FRI EVENING WITH THE PLACEMENT OF THE SURFACE LOW OVER NC FRI AFTERNOON...WITH THE 00Z GFS/00Z GEFS MEAN/00Z ECMWF/12Z ECMWF ENSEMBLE MEAN/00Z UKMET SHOWING TIGHT CLUSTERING WITH THE SURFACE LOW POSITION. AS THE ENTIRE SYSTEM PUSHES INTO THE SOUTHEAST STATES...THE 00Z ECMWF IS THE OUTLIER WITH THE SURFACE LOW POSITION OFF THE NC COAST. THE 00Z GFS/UKMET/GEFS MEAN/12Z ECMWF ENSEMBLE ARE CLUSTERED TIGHTLY WITH A SURFACE LOW POSITION OVER SOUTHERN SC. THE 00Z ECMWF IS DROPPED FROM THE PREFERENCES AFTER FRI EVENING BECAUSE OF THE TIGHT CLUSTERING. EASTERN PORTION OF BROAD MID LEVEL LOW THAT CLOSES OFF INTO ALBERTA WED ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL BLEND CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE 00Z NAM AND 00Z GFS ARE CLOSE WITH THE TIMING OF THE CLOSING OFF OF THE MID LEVEL SYSTEM OVER ALBERTA WED...AND ARE CLOSE TO THE MODEL CONSENSUS. THEREFORE...A GENERAL MODEL BLEND IS PREFERRED. WESTERN PORTION OF BROAD UPPER LOW THAT CLOSED OFF NEAR THE COAST OF OR INTO THU ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: 00Z GFS/00Z ECMWF BLEND CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE 00Z NAM IS CLOSE TO THE MODEL CONSENSUS THROUGH FRI MORNING...BUT IT KEEPS THE MID LEVEL CIRCULATION JUST OFFSHORE. THE 00Z GFS IS A TAD FASTER...BRING THE CIRCULATION JUST ONSHORE BEFORE IS BECOMES QUASI STATIONARY INTO SAT. THESE TWO SOLUTIONS ARE CLOSE TO THE CONSENSUS... AND ARE SUPPORTED BY THE ENSEMBLE MEANS. A 00Z GFS/00Z ECMWF BLEND REPRESENTS THE CONSENSUS POSITION WELL...AND IS THE PREFERRED BLEND WITH THIS SYSTEM. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... HAYES