ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 145 PM EST TUE DEC 23 2014 VALID 12Z SAT DEC 27 2014 - 12Z WED DEC 31 2014 GAINED SOME CONFIDENCE FOR THE FORECAST FOR THE ALASKA REGION AT THE MEDIUM RANGE WITH THE ADVENT OF THE 00Z/23 MODELS. THE OPERATIONAL GFS AND ECMWF WERE NOTABLY CLOSE WITH THE MAJOR SYNOPTIC CYCLONES THROUGH DAY 4, REVEALING PERHAPS THAT THE GLOBAL NUMERICAL GUIDANCE IS FINALLY TUNING INTO A RELIABLE SIGNAL. THE GFS AND ECMWF WERE NOT CLOSE ENOUGH AS A WHOLE TO MERIT A MANUAL BLEND OF THEIR MASS FIELDS, PARTICULARLY BECAUSE THE TRICK OF LATE HAS BEEN TO PRESERVE AS MUCH GRADIENT AS POSSIBLE TO SUPPORT REALISTIC WIND GRIDS. FURTHERMORE, THE GFS CAMP HAS DISTINGUISHED ITSELF FROM THE EC/CANADIAN CAMP WITH A DIFFERENT LOCATION OF THE BUILDING UPPER RIDGE OVER ALASKA AND THE YUKON--A CRITICAL FACTOR FOR THE FORECAST LATE IN THE PERIOD AND INTO THE NEW YEAR. THEREFORE, PREFERRED TO STICK WITH THE LARGER ENSEMBLE CLUSTER THAT CORRELATED WITH THE EUROPEAN CENTRE GUIDANCE. THE 00Z/23 OPERATIONAL ECMWF WAS CLOSE ENOUGH TO ITS ATTENDANT ENSEMBLE MEAN TO PREPOSSESS A ROBUST PERCENTAGE OF THE BLEND--CERTAINLY A BOON FOR THE WIND GRIDS. CISCO