MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 222 AM EDT THU JUL 17 2014 VALID JUL 17/0000 UTC THRU JUL 20/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION...INCLUDING THE NAM/GFS/UKMET/GEM AND ECMWF ...DEEP UPPER TROUGH LIFTING THROUGH THE NORTHEAST THROUGH THURS AND FRI... PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE THE LATEST MODEL GUIDANCE APPEARS SIMILAR WITH THIS FEATURE. ...SHORTWAVE TROUGH EJECTING FROM THE CENTRAL HIGH PLAINS EAST TO THE OH/TN VALLEYS... PREFERENCE: 00Z ECMWF CONFIDENCE: AVERAGE THE MODELS SHOW GOOD AGREEMENT IN TAKING SHORTWAVE ENERGY CURRENTLY OVER THE CO HIGH PLAINS ESEWD AND THEN EWD ACROSS THE S CNTRL PLAINS THURS BEFORE MOVING INTO THE OH/TN VLYS THIS WEEKEND WHEN A SOMEWHAT BROADER AND SLOW MOVING UPR TROUGH SHOULD BE NOTED. THE 00Z UKMET AND 00Z GFS GRADUALLY BECOME SOMEWHAT FASTER SOLNS BY SAT/SUN WITH THE ENERGY MOVING INTO THE ERN U.S...WITH THE 00Z NAM AND TO A LESSER EXTENT THE 00Z GEM THE SLOWEST SOLNS. THE 00Z ECMWF SPLITS THE DIFF. WILL FAVOR THE 00Z ECMWF ATTM. ...DEEP UPPER TROUGH DEVELOPING OVER THE GULF OF AK AND IMPACTING THE NORTHWEST... PREFERENCE: BLEND OF THE 00Z GFS/00Z ECMWF CONFIDENCE: AVERAGE THE MODELS TAKE A RATHER ZONAL FLOW PATTERN INITIALLY OVER THE THE GULF OF AK AND WRN CANADA AND AMPLIFY IT RATHER SHARPLY THIS WEEKEND WITH A LARGE UPR TROUGH DEVELOPING ALONG WITH A PAIR OF CLOSED LOWS THAT WILL TRAVERSE NRN PORTIONS OF THE GULF OF AK AND MOVE INTO BRITISH COLUMBIA. THE SRN EXTENT OF THE UPR TROUGH WILL MOVE INTO THE NORTHWEST U.S. ON SUN. THE 00Z NAM IS FASTEST WITH THE EWD ADVANCE OF ENERGY INTO WRN CANADA...WITH THE 00Z GEM THE SLOWEST. THE 00Z UKMET/00Z ECMWF AND 00Z GFS SPLIT THE DIFF. THE STRONGER MODEL CLUSTERING TENDS TO RESIDE WITH THE GFS/ECMWF CAMP AND SO A BLEND OF THESE SOLNS WILL BE PREFERRED. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ORRISON