MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1111 PM EST MON MAR 03 2014 VALID MAR 04/0000 UTC THRU MAR 07/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION...INCLUDING THE NAM AND GFS ...UPPER LOW OVER WRN CANADA...SHIFTING EAST THROUGH THE WEEK... PREFERENCE: BLEND OF THE 00Z GFS/12Z ECMWF CONFIDENCE: AVERAGE THE MODELS GRADUALLY TAKE THE NEARLY STATIONARY UPR LOW OVER WRN BRITISH COLUMBIA EASTWARD OVER THE NEXT COUPLE OF DAYS AND WEAKENING INTO A MORE PROGRESSIVE SHORTWAVE TROUGH OVER CNTRL CANADA BY THURS AND CROSSING HUDSON/JAMES BAY BY FRI. THE 00Z NAM OVERALL SUGGESTS A SOMEWHAT DEEPER SOLN COMPARED TO THE MULTI-MODEL CONSENSUS. THE 12Z UKMET AND 12Z GEM GLOBAL TEND TO BE A LITTLE SLOWER THAN THE CONSENSUS OF SOLNS...WITH THE 00Z GFS AND 12Z ECMWF ACTUALLY CLUSTERING VERY WELL ON A SOLN THAT IS A TAD FASTER. THE LATEST GEFS MEAN/ECENS MEAN AND SREF MEAN SUPPORT THE IDEA OF THE TROUGH BECOMING MORE PROGRESSIVE BY THU/FRI...WHICH SUPPORTS THE GFS/ECMWF CLUSTER. SO BASED ON THE STRONG ENSEMBLE SUPPORT...WILL PREFER A BLEND OF THE GFS AND ECMWF. ...WEAK MID LEVEL TROUGH CROSSING THE SRN PLAINS/SOUTHEAST TUE AND WED... PREFERENCE: BLEND OF THE 00Z GFS/12Z ECMWF CONFIDENCE: AVERAGE THE 00Z NAM AND 12Z UKMET ARE THE FLATTER/WEAKER SOLNS WITH THE MID LVL WAVE COMPARED TO THE REMAINING MODELS TUE AS THE ENERGY MOVES OUT OF THE SRN PLAINS AND ACROSS THE GULF COAST STATES OVER THE NEXT COUPLE OF DAYS. THE 00Z GFS AND THE 12Z GEM GLOBAL/12Z ECMWF SOLNS ARE A TAD STRONGER/DEEPER. THE LATEST GEFS MEAN AND ESP THE ECENS MEAN SUPPORT A TAD MORE AMPLITUDE WITH THIS EJECTING SHORTWAVE TROUGH. WILL PREFER A BLEND OF THE GFS AND ECMWF. ...STRENGTHENING MID/UPPER LEVEL TROUGH REACHING THE GULF COAST STATES/SOUTHEAST WED THROUGH FRI... ...SURFACE CYCLOGENESIS OVER THE NERN GULF OF MEXICO...LIFTING UP OFF THE SOUTHEAST/MID-ATLANTIC... PREFERENCE: BLEND OF THE 00Z GFS/12Z ECMWF/12Z ECENS MEAN CONFIDENCE: BELOW AVERAGE THE 00Z NAM HAS TRENDED SLOWER AND STRONGER WITH THE HEIGHT FALLS ASSOCD WITH THIS SHORTWAVE ENERGY DIGGING DOWN ACROSS THE CNTRL/SRN PLAINS AND TWD THE GULF COAST STATES/SOUTHEAST WED THROUGH FRI...BUT IT IS OVERALL THE WEAKEST SOLN REGARDING TROUGH DEPTH COMPARED TO THE OTHER GLOBAL MODELS. THE 00Z NAM ALSO APPEARS A LITTLE TOO WEAK WITH ITS SFC CYCLOGENESIS OVER THE NERN GULF OF MEXICO AND OFFSHORE THE SOUTHEAST AND MID-ATLANTIC STATES BY FRI. THE 12Z UKMET FOR ITS PART APPEARS TOO STRONG WITH ITS HEIGHT FALLS AND IS A LITTLE TOO FAST. IT HAS A NOTABLY STRONGER SFC LOW DEVELOPING AND RIDING NEWD UP OFFSHORE THE SOUTHEAST COASTLINE AND IS TUCKED IN CLOSER TO THE NC OUTER BANKS BY EARLY FRI. THE 12Z GEM GLOBAL APPEARS TOO FAR NORTH AT LEAST BY EARLY FRI WITH ITS SFC LOW. THE 00Z GFS AND 12Z ECMWF SHOW THE STRONGEST AGREEMENT WITH THE MASS FIELDS ALOFT...BUT AT THE SFC...THE GFS DEVELOPS ITS SFC LOW A LITTLE FARTHER EAST OFFSHORE THE SOUTHEAST COMPARED TO THE ECMWF AND ACTUALLY APPEARS TO BE A BIT TOO WEAK. THE LATEST GEFS MEAN THOUGH DOES TEND TO SUPPORT A RELATIVELY WEAKER SFC LOW...BUT THE ECENS MEAN SUGGESTS A STRONGER LOW. WILL PREFER A BLEND OF THE GFS/ECMWF AND THE LATEST ECENS MEAN BASED ON THEIR OVERALL MASS FIELD CLUSTERING...BUT GIVEN THE OVERALL MODEL SPREAD WITH THE SFC LOW OFFSHORE THE SOUTHEAST AND MID-ATLANTIC BY EARLY FRI...CONFIDENCE IS LIMITED. ...NRN STREAM MID LEVEL SHORTWAVE AFFECTING THE GREAT LAKES TO THE NORTHEAST ON WED AND THU... PREFERENCE: BLEND OF THE 18Z GEFS MEAN/12Z ECENS MEAN CONFIDENCE: BELOW AVERAGE THERE HAS BEEN TERRIBLE RUN TO RUN MODEL CONTINUITY WITH THIS SYS...BUT AT LEAST THE LATEST MODELS ARE FINALLY CONVERGING ON A SOLN THAT IS MORE PROGRESSIVE/SHEARED THROUGH THE REGION AND INTO SERN CANADA WED AND THU. THE 00Z GFS IS THE MOST PROGRESSIVE WITH THE 12Z ECMWF AND 12Z GEM GLOBAL THE SLOWEST. THE 00Z NAM AND 12Z UKMET SPLIT THE DIFF. THE LATEST GEFS MEAN AND ECENS MEAN SUPPORT THEIR RESPECTIVE DETERMINISTIC SOLNS. WILL CONTINUE TO FAVOR A BLEND OF THE ENSEMBLE MEANS GIVEN THE POOR MODEL CONTINUITY WITH THE DETERMINISTIC SOLNS. ...SHORTWAVE TROUGH/SURFACE LOW APPROACHING THE PACIFIC NORTHWEST BY THU... PREFERENCE: BLEND OF THE 00Z GFS/00Z ECMWF CONFIDENCE: AVERAGE THE MODELS INDICATE A SHORTWAVE TROUGH AND ATTENDANT SFC LOW/FRONT APPROACHING THE PAC NORTHWEST BY EARLY THU AND PUSHING INLAND THU NIGHT AND FRI. THE 12Z UKMET APPEARS TO BE A LITTLE TOO PROGRESSIVE WITH THE 12Z GEM GLOBAL THE SLOWEST. THE 00Z NAM IS ALSO AT LEAST INITIALLY TOO SLOW AS WELL...BUT THEN COMES INTO BETTER TIMING AGREEMENT WITH THE MULTI-MODEL CONSENSUS BY FRI AS THE ENERGY ADVANCES WELL INLAND. OVERALL THE 00Z GFS AND 12Z ECMWF SPLIT THE DIFF...BUT CLUSTER WELL AND HAVE GOOD ENSEMBLE SUPPORT FROM THE LATEST GEFS MEAN AND ECENS MEAN. THEREFORE...A BLEND OF THE GFS/ECMWF SOLNS APPEARS REASONABLE AT THIS TIME. www.wpc.ncep.noaa.gov/html/model2.shtml... ORRISON