ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 203 PM EDT MON JUN 23 2014 VALID 12Z FRI JUN 27 2014 - 12Z TUE JUL 01 2014 IN A MANNER SIMILAR TO THAT DESCRIBED YESTERDAY...A CLOSED MID-UPPER LEVEL LOW AND MOST ASSOCIATED PCPN/WEATHER ANCHORING OVER THE GULF OF ALASKA WILL BE PERIODICALLY REINFORCED BY BERING SEA/ALEUTIANS IMPULSES. THIS ESTABLISHED FEATURE POSITION LEADS TO WARMING MID-UPPER LEVEL RIDGE BUILDING OVER THE TOP INTO THE INTERIOR/ARCTIC CIRCLE FROM THE WEEKEND INTO NEXT WEEK IN ERNEST IN THE WAKE OF EARLIER PERIOD EMBEDDED IMPULSE PASSAGE. THE DETERMINISTIC MODELS SHOW LESS FORECAST SPREAD THAN YESTERDAY INTO THE WEEKEND WITH THE SMALLER-SCALE DETAILS FOR ESPECIALLY THE INTERIOR/ARCTIC CIRCLE WHWERE LOCAL PCPN FOCUSING MIGRATING WAVES ALOFT WORK OVER THE NRN PERIPHERY OF THE GULF OF ALASKA CIRCULATION. MEANWHILE...THE ENERGY TRANSFER ALONG THE SRN QUADRANTS OF THE GYRE ALSO DISPLAYED ENOUGH SPREAD TO MAKE SUSPECT MUCH OF THE DETERMINISTIC DETAILS BY NEXT WEEK...BUT ARE BETTER CLUSTERED NOW PRIOR TO THAT. ACCORDINGLY...THE WPC ALASKAN MEDIUM-RANGE PRODUCT SUITE WAS PRIMARILY DERIVED FROM A COMPOSITE BLEND OF OVERALL COMPATABLE GUIDANCE FROM THE 00 UTC GFS/ECMWF AND GEFS/NAEFS/ECMWF ENSEMBLE MEANS DAYS 4-6 FRI-SUN. THE 12 UTC GFS DRIFTED OFF THE MODEL CONCENSUS SOME AND WAS NOT INCLUDED FOR THAT REASON. SLOWLY INCREASING FORECAST SPREAD SUGGESTED USAGE OF JUST THE 00 UTC GFS/NAEFS/ECMWF ENSEMBLE MEANS FOR DAYS 7/8...BUT PREDICTABILITY STILL SEEMS AVERAGE OR EVEN BETTER THAN NORMAL. THIS DAYS 4-8 FORECAST SCENARIO MAINTAINS GOOD WPC CONTINUITY...ALBEIT WITH A BETTER ORGANIZED GULF OF ALASKA SURFACE LOW THROUGH THE PERIOD GIVEN IMPROVED MODEL CONSENSUS AND SUPPORT ALOFT. SCHICHTEL