MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1116 PM EST FRI MAR 04 2016 VALID MAR 05/0000 UTC THRU MAR 08/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION...INCLUDING THE NAM AND GFS ...SHORTWAVE/CLIPPER LOW DIGGING ACROSS THE MIDWEST... ...ENERGY CROSSING THE OH VALLEY/MID-ATLANTIC THROUGH SUN... PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE AFTER A MULTI-DAY TREND TO SHIFT THE VORT/SURFACE WAVE TRACK A BIT FARTHER SOUTH...THE MODELS ARE NOW VERY WELL CLUSTERED WITH THIS SYSTEM. SO WILL PREFER A GENERAL MODEL COMPROMISE. ...SURFACE LOW LIFTING JUST OFF THE PACIFIC NORTHWEST EARLY SAT... PREFERENCE: NON-UKMET CONSENSUS CONFIDENCE: ABOVE AVERAGE THE FIRST IN A SERIES OF SHORTWAVE IMPULSES/SURFACE LOWS IMPACTING THE NORTHWEST WILL BE LIFTING OFFSHORE WA/OR EARLY ON SAT AND AIMING TOWARD COASTAL BRITISH COLUMBIA. THE 12Z UKMET IS A BIT OF A SLOW/DEEP OUTLIER WITH THE INITIAL WAVE...WITH THE REMAINING GUIDANCE WELL CLUSTERED AROUND A SOMEWHAT FASTER SOLUTION. WILL PREFER A NON-UKMET CONSENSUS WITH THIS FIRST WAVE. ...SHORTWAVE/SURFACE LOW IMPACTING THE WEST COAST LATE SAT/SUN... ...ATTENDANT FRONTAL ZONE MOVING THROUGH CA/GREAT BASIN... PREFERENCE: 12Z ECMWF CONFIDENCE: AVERAGE A WELL-DEFINED SHORTWAVE AND ASSOCIATED SURFACE WAVE WILL IMPACT THE WEST COAST LATE SAT WITH A SURFACE LOW RAPIDLY DEEPENING OFFSHORE THE PACIFIC NORTHWEST SAT NIGHT. THIS WILL SEND A COLD FRONT ACROSS CA AND THROUGH THE GREAT BASIN SAT NIGHT AND SUN. LIKE ITS PREDECESSOR...THE 12Z UKMET IS A BIT SLOWER AND DEEPER THAN THE MULTI-MODEL CONSENSUS WITH THE SURFACE LOW. THE 00Z NAM AND 00Z GFS ARE A LITTLE FARTHER WEST WITH ITS SURFACE LOW TRACK VERSUS 12Z CMC AND 12Z ECMWF. THE LATEST GEFS MEAN AND ECENS MEAN ARE MORE SUPPORTIVE OF A NON-NCEP CONSENSUS LED PREDOMINANTLY BY THE ECMWF...AND SO WILL LEAN TOWARD THE 12Z ECMWF WHICH WAS ALSO SUPPORTED BY THE 18Z GFS. ...SHORTWAVE/SURFACE LOW IMPACTING THE WEST COAST SUN NIGHT/MON... ...UPPER TROUGH/CLOSED LOW AMPLIFYING OVER THE SOUTHWEST MON/TUES... PREFERENCE: BLEND OF THE 00Z GFS/12Z UKMET AND 12Z ECMWF CONFIDENCE: SLIGHTLY BELOW AVERAGE THE MODELS SHOW A STRONG SHORTWAVE AMPLIFYING INTO THE WEST COAST SUN NIGHT AND MON...WITH A SURFACE LOW MOVING INTO FAR NORTHERN CA/SOUTHWEST OR. THE MODELS THEN DIG THIS ENERGY SHARPLY SOUTHEAST INTO THE SOUTHWEST MON/TUES WITH A ROBUST CLOSED MID LEVEL LOW CENTER DROPPING INTO NORTHWEST MEXICO BY TUES. THE 00Z GFS/12Z ECMWF AND 12Z UKMET ARE MOST PROGRESSIVE AND A BIT FLATTER WITH THE LOW CENTER MOVING INLAND SUN NIGHT ALONG WITH THE ATTENDANT FRONTAL ZONE. THE 00Z NAM AND 12Z CMC ARE SLOWER AND GENERALLY MORE AMPLIFIED. GIVEN THE 00Z GFS TREND TO BE MORE PROGRESSIVE LIKE THE ECMWF/UKMET CLUSTER...WILL LEAN TOWARD A CONSENSUS OF THE GFS/UKMET/ECMWF WITH THIS SYSTEM WHICH INCLUDES THE CLOSED LOW DEVELOPMENT INTO THE SOUTHWEST/NORTHWEST MEXICO MON AND TUES. ...DEVELOPING LOW PRESSURE OVER THE NORTHERN HIGH PLAINS SUN/MON... ...COLD FRONT EJECTING ACROSS THE NORTHERN PLAINS/UPPER MIDWEST... PREFERENCE: BLEND OF THE 00Z GFS/12Z CMC AND 12Z ECMWF CONFIDENCE: AVERAGE LEAD SHORTWAVE ENERGY TRAVERSING THE INTERMOUNTAIN WEST ON SUN WILL BE EJECTING OUT INTO THE HIGH PLAINS ON MON AND WILL FOSTER CYCLOGENESIS OVER THE MT HIGH PLAINS BY SUN NIGHT. THE 00Z NAM IS SLOWER THAN THE MULTI-MODEL CONSENSUS WITH THE LOW PRESSURE EVOLUTION. THE 12Z CMC/12Z ECMWF AND 00Z GFS ARE CLUSTERED A LITTLE FASTER...WITH THE 12Z UKMET OVERALL THE MOST PROGRESSIVE AND ALSO TRACKING ITS SURFACE LOW A TAD NORTH OF THE MULTI-MODEL CONSENSUS. WILL FAVOR A BLEND OF THE GFS/CMC AND ECMWF BASED ON THEIR STRONGER MODEL CLUSTERING. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ORRISON