MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 135 AM EST WED MAR 05 2014 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/GFS/UKMET/GEM GLOBAL AND THE ECMWF ...SHORTWAVE TROUGH DROPPING THROUGH NEW ENGLAND BY LATE WEDNESDAY... PREFERENCE: NON-NAM CONSENSUS CONFIDENCE: ABOVE AVERAGE THE MODELS ARE IN RATHER GOOD AGREEMENT NOW WITH THE THE ELONGATED AXIS OF SHORTWAVE ENERGY THAT IS EXPECTED TO DROP SEWD ACROSS ONTARIO/QUEBEC AND ADVANCE THROUGH NEW ENGLAND. THE 00Z NAM THOUGH IS SOMEWHAT OF A STRONG OUTLIER WITH THE HEIGHT FALLS...WITH THE REMAINING MODELS WELL CLUSTERED WITH TIMING AND DEPTH. WILL FAVOR A NON-NAM CONSENSUS WITH THIS SYS. ...UPPER TROUGH/CLOSED LOW DEVELOPMENT ACROSS THE GULF COAST STATES AND SOUTHEAST U.S... ...INITIAL SURFACE WAVE IN THE GULF OF MEXICO... ...COASTAL LOW DEVELOPING ALONG THE SOUTHEAST U.S. COAST... PREFERENCE: BLEND OF THE 00Z GFS/00Z ECMWF/00Z UKMET CONFIDENCE: AVERAGE SHORTWAVE ENERGY EJECTING OUT OF THE CNTRL GRT BASIN/ROCKIES WILL GRADUALLY AMPLIFY INTO A SIGNIFICANT UPPER TROUGH AND LIKELY A CLOSED LOW OVER THE GULF COAST STATES AND SOUTHEAST THU AND FRI. ALL THE WHILE THIS WILL FOSTER SFC CYCLOGENESIS INITIALLY OVER THE GULF OF MEXICO...WITH LOW PRESSURE THEN ADVANCING NEWD AND INTENSIFYING OFF THE SOUTHEAST COAST ON FRI. THE LOW CENTER IS THEN EXPECTED TO ADVANCE NEWD AND EAST OF THE MID-ATLANTIC STATES ON SAT. THE 00Z NAM AND ESP THE 00Z GEM GLOBAL ARE STRONG OUTLIER SOLNS...WITH A CONSIDERABLY MORE AMPLIFIED SOLN THAN THE MULTI-MODEL CONSENSUS OVER THE ENTIRE GULF COAST AND SOUTHEAST. THESE MODELS ARE TIMING OUTLIERS TOO...WITH THE NAM BEING THE SLOWEST SOLN AND THE GEM GLOBAL THE FASTEST. THE NAM AND GEM GLOBAL SUGGEST SFC LOW TRACKS THAT ARE WELL LEFT OF THE CONSENSUS OF SOLNS...AND IN THE CASE OF THE NAM...IT IS SO FAR LEFT THAT IT HAS A LOW ACTUALLY MOVING INLAND FRI NIGHT/SAT ACROSS ERN NC AND INTO SERN VA. THE 00Z GFS FOR ITS PART HAS NOW TRENDED OVERALL VERY STRONGLY TWD THE MORE CONSISTENT 00Z ECMWF AND 00Z UKMET WITH RESPECT TO HEIGHT FALLS/TIMING AND SFC LOW DETAILS. THE GFS/UKMET/ECMWF CAMP SPLITS THE DIFF BETWEEN THE SLOW NAM AND FAST GEM GLOBAL. THE 12Z ECENS MEAN AND 00Z GEFS MEAN SUPPORT THE GFS/ECMWF/UKMET CLUSTER. BASED ON THE LATEST MODEL TRENDS/CLUSTERING AND ENSEMBLE SUPPORT...WILL FAVOR A BLEND OF THE GFS/UKMET/ECMWF SOLNS WITH AVERAGE CONFIDENCE. ...PROGRESSIVE SHORTWAVE TROUGH ADVANCING THROUGH THE NORTHWEST EARLY THU... ...MEAN TROUGH/POSSIBLE CLOSED LOW DEVELOPMENT ACROSS THE FOUR CORNERS BY FRI AND SAT... PREFERENCE: NON-NAM CONSENSUS CONFIDENCE: AVERAGE THE MODELS INDICATE A STRONG SHORTWAVE TROUGH AND ASSOCD SFC LOW ADVANCING RAPIDLY INTO THE NORTHWEST U.S. BY THU...WITH THE ENERGY THEN EXPECTED TO BEGIN DIGGING AND AMPLIFYING SEWD THROUGH THE GRT BASIN ON ITS WAY TO THE FOUR CORNERS REGION FRI AND SAT. THE 00Z NAM IS A SLOW AND RELATIVELY WEAK OUTLIER SOLN WITH THIS SYS AND WILL BE DISCOUNTED. THE 00Z GFS AND THE 00Z UKMET/00Z GEM GLOBAL AND 00Z ECMWF SOLNS ARE ALL STRONGER AND BY FRI AND SAT SUGGEST CLOSED LOW DEVELOPMENT INVOF THE FOUR CORNERS AREA AND POSSIBLY THE SRN HIGH PLAINS. THE 00Z ECMWF WITH SUPPORT FROM THE 12Z ECENS MEAN IS A TAD FASTER TO PROGRESS THE ENERGY TWD THE HIGH PLAINS BY SAT. THE 00Z GFS/00Z GEM GLOBAL AND 00Z UKMET WITH SUPPORT FROM THE 00Z GEFS MEAN ARE A LITTLE SLOWER WITH ENERGY TENDING TO LINGER A LITTLE MORE OVER THE CNTRL/SRN ROCKIES. WILL SUGGEST A COMPROMISE ATTM BETWEEN THE SLOWER AND FASTER CAMPS...AND DISCOUNTING THE NAM. THEREFORE...A NON-NAM CONSENSUS WILL BE PREFERRED. ...NEXT SURGE OF COLDER AIR SETTLING DOWN INTO THE NORTHERN U.S. THROUGH FRI AND SAT... PREFERENCE: NON-NAM CONSENSUS CONFIDENCE: AVERAGE THE NEXT NRN STREAM TROUGH LATE IN THE PERIOD SHOULD GENERALLY JUST CLIP THE NRN PLAINS/UPR MIDWEST AND GRT LAKES REGION OVER THE NEXT COUPLE OF DAYS...BUT WILL BE RESPONSIBLE FOR SENDING ANOTHER COLD FRONT SEWD WITH A REINFORCING SHOT COLD AIR DOWN ACROSS MUCH OF THE NRN PLAINS AND MIDWEST AFTER A BRIEF WARM-UP. THE 00Z NAM IS A RELATIVELY SLOW OUTLIER SOLN WITH THE SHORTWAVE ENERGY CLIPPING THE REGION. THE REMAINING MODELS CLUSTER WELL WITH THE ENERGY ALOFT WITH RESPECT TO TIMING/DEPTH AND WITH THE FRONTAL DETAILS. WILL FAVOR A NON-NAM CONSENSUS. www.wpc.ncep.noaa.gov/html/model2.shtml... ORRISON