MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1148 AM EST FRI FEB 21 2014 VALID FEB 21/1200 UTC THRU FEB 25/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z MODEL EVALUATION...INCLUDING THE NAM AND GFS ...FRONT APPROACHING THE PACIFIC NORTHWEST SUNDAY NIGHT... PREFERENCE: BLEND OF THE 12Z GFS AND 00Z ECMWF CONFIDENCE: AVERAGE A WEAK FRONT WILL APPROACH THE PAC NORTHWEST SUN NIGHT...BUT THE MAIN FOCUS OF THE ENERGY AND FORCING WITH THE FRONT IS EXPECTED TO STAY OFFSHORE AND LIFT NEWD WHILE WEAKENING AHEAD OF A STRONGER LOW CENTER UPSTREAM SOUTH OF THE ALEUTIANS. THE 00Z UKMET AND 00Z GEM GLOBAL APPEAR A LITTLE DEEPER THAN THE GLOBAL MODEL CONSENSUS WITH A WAVE OF LOW PRESSURE ADVANCING ALONG THIS FRONT JUST OFFSHORE THE WA/ORE COAST. PREFER THE RELATIVELY WEAKER AND STRONGER MODEL CLUSTERING OF THE 12Z GFS AND 00Z ECMWF. ...SHORTWAVE MOVING THROUGH CALIFORNIA ON SUNDAY... PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE THE GUIDANCE SHOWS GOOD AGREEMENT WITH THIS WEAK FEATURE. A GENERAL MODEL COMPROMISE IS PREFERRED TO RESOLVE ANY LINGERING SMALL SCALE DIFFS. ...SHORTWAVE DIGGING INTO THE NORTHERN PLAINS/UPPER MIDWEST BY LATE MONDAY... PREFERENCE: BLEND OF THE 12Z GFS/00Z ECMWF CONFIDENCE: AVERAGE A SHORTWAVE TROUGH WILL BE DROPPING DOWN FROM SRN CANADA ON MON AND DIGGING INTO THE NRN PLAINS AND UPR MIDWEST BY LATE MON. THE 12Z GFS AND 00Z ECMWF CLUSTER THE BEST WITH THIS SYS...WITH THE 00Z UKMET A SLOW OUTLIER AND THE 12Z NAM AND TO A LESSER EXTENT THE 00Z GEM GLOBAL WEAKER OUTLIERS. ...SHORTWAVE MOVING INTO OHIO VALLEY/NORTHEAST SUNDAY NIGHT... ...SURFACE LOW OFFSHORE NEW ENGLAND MONDAY MORNING... PREFERENCE: BLEND OF THE 00Z GEM GLOBAL/00Z ECMWF CONFIDENCE: BELOW AVERAGE THE 12Z NAM AND ESP THE 00Z UKMET SOLNS ARE STRONG OUTLIERS WITH THE SHORTWAVE TROUGH/SFC LOW CROSSING THE OH VLY AND NORTHEAST AND OFFSHORE NEW ENGLAND SUN THROUGH MON. ITS 500 HPA SHORTWAVE IN THREE DAYS...WITH THE 00Z UKMET THE SLOWEST AND DEEPEST. THE 12Z GFS IS THE FASTEST/WEAKEST SOLNS. THE 00Z GEM GLOBAL AND 00Z ECMWF SPLIT THE DIFF BUT CLUSTER TOGETHER RATHER WELL. THE 00Z ECENS MEAN AND 06Z GEFS MEAN OVERALL TEND TO SUPPORT THE 00Z ECMWF...BUT HAVE THEIR SFC LOW POSITIONS A LITTLE NORTH OF THE ECMWF/GEM GLOBAL CAMP. WILL FAVOR THE ECMWF/GEM SOLNS ATTM...BUT WITH LIMITED CONFIDENCE GIVEN THE OVERALL MODEL SPREAD. ...DEEP CYCLONE EXITING THE GREAT LAKES AND MOVING INTO CANADA... PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE THE GUIDANCE IS IN GOOD AGREEMENT WITH THIS SYSTEM EXITING THE GREAT LAKES REGION AND MOVING INTO ONTARIO AND QUEBEC OVER THE NEXT COUPLE OF DAYS. A GENERAL MODEL COMPROMISE IS PREFERRED. www.wpc.ncep.noaa.gov/html/model2.shtml... ORRISON