ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 230 PM EDT SAT MAY 23 2015 VALID 12Z WED MAY 27 2015 - 12Z SUN MAY 31 2015 FOR THE MAINLAND AND PANHANDLE... ENERGY REACHING THE SRN COAST LATE IN THE SHORT RANGE TIME FRAME HAS TRENDED MORE CLOSED IN LATEST RUNS. BY THE EXTENDED TIME FRAME IT BECOMES INCREASINGLY DIFFICULT TO RESOLVE WHAT THIS FEATURE WILL DO AS IT ESSENTIALLY BECOMES EMBEDDED WITHIN THE LARGE SCALE MEAN RIDGE. SOLNS RANGE FROM CONTINUED PROGRESSION IN THE 00Z ECMWF/CMC TO AN EVENTUAL NWWD/WWD DRIFT IN RECENT GFS RUNS. CURRENTLY FAVOR THE ENSEMBLE MEANS TO YIELD A WEAKER SOLN GIVEN THE SURROUNDING MEAN RIDGE AND CONSIDERABLE SPREAD. REGARDING THE UPR RIDGE THE ENSEMBLE MEANS HAVE GENERALLY BEEN MORE CONSISTENT/AGREEABLE RELATIVE TO OPERATIONAL MODEL RUNS. AS SPORADIC MODEL RUNS HAVE ADVERTISED THOUGH... LATEST GEFS MEANS SHOW GREATER POTENTIAL THAN OTHER MEANS FOR A CLOSED HIGH TO FORM DURING A PORTION OF THE PERIOD AND WITH HIGHER HGTS. GIVEN ENSMEAN TRENDS OVER THE PAST 36 HRS TOWARD A STRONGER RIDGE IT SEEMS REASONABLE TO INCLUDE AT LEAST SOME WEIGHTING OF THE 06Z GEFS MEAN AND COMPROMISE 00Z NAEFS MEAN ALONG WITH THE 00Z ECMWF MEAN. THERE IS MINIMAL SUPPORT FOR THE 00Z ECMWF THAT BRINGS SIGNIFICANT HGT FALLS/COMPACT CLOSED LOW INTO THE MAINLAND FROM THE NORTHEAST NEXT WEEKEND. MEANWHILE GUIDANCE CONTINUES TO BE CHALLENGED BY EVOLUTION ACROSS THE BERING SEA/ALEUTIANS/NRN PACIFIC. A RELATIVE CONSENSUS APPEARS TO HAVE FORMED FOR THE LEADING BERING SEA SYSTEM THAT HAD CONSIDERABLE SPREAD 24 HRS AGO... KEEPING THE SFC LOW ON THE WRN SIDE OF THE PRIOR SOLN ENVELOPE. MODELS/INDIVIDUAL ENSEMBLE MEMBERS STILL VARY WIDELY FOR THE NRN PAC SYSTEM EXPECTED TO APPROACH THE ALEUTIANS WED-THU. 00Z/06Z GFS RUNS ARE MORE SIMILAR TO RUNS FROM 12-24 HRS EARLIER AS WELL AS PRIOR ECMWF RUNS IN BRINGING THE SYSTEM INTO THE BERING SEA. HOWEVER THERE IS A NOTABLE SWD TREND IN LATEST GEFS/ECMWF MEANS AS WELL AS THE 00Z ECMWF. CMC RUNS HAVE BEEN S OF THE ALEUTIANS FOR AT LEAST THE PAST 2-3 CYCLES. CONFIDENCE REMAINS BELOW AVG BUT HINTS AT FURTHER RETROGRESSION/WWD BUILDING OF THE MAINLAND RIDGE PLUS SIGNIFICANT CHANGES IN THE 12Z GFS RUN/CONTINUITY IN THE CMC AT LEAST PROVIDE ADDED SUPPORT FOR SOME SWD ADJUSTMENT FROM YDAYS ENSMEAN CONSENSUS. ACCOUNTING FOR THE ABOVE CONSIDERATIONS... THE FCST THROUGH THE DAYS 4-8 WED-SUN PERIOD STARTS WITH A 60/20/20 BLEND OF THE 00Z ECMWF MEAN/00Z NAEFS MEAN/06Z GEFS MEAN WITH MINOR ADJUSTMENTS AS NEEDED. RAUSCH