MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1243 PM EDT SAT MAY 03 2014 VALID MAY 03/1200 UTC THRU MAY 07/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z MODEL EVALUATION...INCLUDING THE NAM AND GFS ...UPPER TROUGH/CLOSED LOW IMPACTING THE WESTERN U.S.... PREFERENCE: NON-UKMET CONSENSUS CONFIDENCE: ABOVE AVERAGE THE 00Z UKMET OVERALL IS A LITTLE DEEPER THAN THE GLOBAL MODEL CONSENSUS...BUT ALL OF THE MODELS INDICATE A ROBUST UPPER TROUGH DIGGING SEWD ACROSS THE GREAT BASIN MON AND TUES. WILL PREFER A NON-UKMET CONSENSUS ATTM SINCE THE REMAINING MODELS CLUSTER VERY WELL. ...UPPER LOW CROSSING THE NORTHEAST ON SUN... ...SURFACE LOW CROSSING MAINE AND EXITING INTO NOVA SCOTIA... PREFERENCE: GENERAL MODEL CONSENSUS CONFIDENCE: ABOVE AVERAGE THE 12Z NAM AND 12Z GFS ARE A TAD STRONGER OVERALL THAN THE 00Z ECMWF/00Z UKMET AND 00Z GEM WITH THE HANDLING OF THE STRONG UPPER LOW AND ASSOCD SURFACE LOW THAT CROSSES THE REGION THROUGH SUN. THE LATEST GEFS MEAN AND ECENS MEAN TEND TO SPLIT THE DIFF...BUT GIVE RELATIVELY MINIMAL SPREAD OVERALL...WILL FAVOR A GENERAL MODEL CONSENSUS. ...SHORTWAVE DIGGING ACROSS THE GREAT LAKES/MID-ATLANTIC/NORTHEAST MON AND TUES... ...WEAK SURFACE LOW THAT CROSSES LOWER OH VALLEY/SOUTHERN MID-ATLANTIC MON AND TUES... PREFERENCE: 00Z ECMWF CONFIDENCE: ABOVE AVERAGE THE SHOW RATHER GOOD AGREEMENT IN ALLOWING A NRN STREAM SHORTWAVE TROUGH TO DIG ACROSS THE GREAT LAKES REGION BEGINNING MON AND THEN INTO THE INTERIOR OF THE NORTHEAST AND MID-ATLANTIC BY TUES. THE MODELS SUGGEST SUFFICIENT INTERACTION WITH A FRONTAL ZONE OVER THE OH VLY AND SRN PORTIONS OF THE MID-ATLANTIC FOR THEIR TO BE A WEAK WAVE OF LOW PRESSURE TRAVERSING THE BNDRY. THE 12Z GFS IS OVERALL THE MOST PROGRESSIVE SOLN WITH THE 00Z GEM THE SLOWEST. THE 12Z NAM IS THE DEEPEST WITH THE TROUGH AXIS...WITH THE 00Z UKMET THE WEAKEST. WILL PREFER THE 00Z ECMWF WHICH OFFERS A NICE COMPROMISE SOLN. ...SHORTWAVE CROSSING FLORIDA THIS WEEKEND... PREFERENCE: GENERAL MODEL CONSENSUS CONFIDENCE: ABOVE AVERAGE THE GUIDANCE IS IN EXCELLENT AGREEMENT WITH THIS SYS AND SO WILL PREFER A GENERAL MODEL CONSENSUS. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ORRISON