ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 319 PM EDT SAT AUG 27 2016 VALID 12Z WED AUG 31 2016 - 12Z SUN SEP 04 2016 ...GUIDANCE/UNCERTAINTY ASSESSMENT AND WEATHER HIGHLIGHTS/THREATS... AN AMPLIFIED MID-UPPER LEVEL FLOW PATTERN NEAR ALASKA SHOULD BE HIGHLIGHTED MIDWEEK BY A BERING STRAIT/ERN BERING SEA RIDGE BETWEEN CLOSED LOWS/TROUGHS NEAR THE WRN ALEUTIANS AND ERN GULF OF AK. LEAD ENERGY ALOFT AND AN ASSOCIATED SURFACE LOW WILL DIG SLOWLY SEWD TO FOCUS PCPN AND UNSETTLED WEATHER WED/THU OVER THE ERN GULF OF AK/SERN AK. THIS LEAVES A LESS DEFINED WEAKNESS ALOFT OVER THE ALASKAN INTERIOR AS THE AFOREMENTIONED BERING STRAIT RIDGE RETROGRADES INTO NERN RUSSIA. MEANWHILE...THE EXTRATROPICAL TRANSITION OF TYPHOON LIONROCK OFF ERN ASIA SHOULD HELP AMPLIFY THE OVERALL DOWNSTREAM FLOW FROM THE MID TO UPPER LATITUDES. THIS SHOULD FAVOR A LESS PROGRESSIVE TREND FOR SIGNIFICANT MID-LATE WEEK DOWNSTREAM LOW DEVELOPMENT NEAR THE WRN ALEUTIANS. PREFER AN ENSEMBLE MEAN BASED SOLUTION WITH EMPHASIS ON THE 00 UTC NAEFS ENSEMBLE MEAN TO BEST MATCH CONTINUITY AND FAVORED SLOWED PROGRESSION TREND. RECENT GEFS/ECMWF ENSEMBLE MEANS ARE ALSO GENERALLY IN LINE EVEN THOUGH AMPLE DETERMINISTIC MODEL RUN TO RUN VARIANCE REMAINS. THIS SIGNIFICANT LOW MAY GRADUALLY WORK INTO SRN BERING SEA BY NEXT WEEKEND IN AMPLIFIED FLOW AND SPREAD WIDESPREAD UNSETTLED WEATHER/RAINFALL DOWNSTREAM ACROSS THE ALEUTIANS/BERING SEA INTO SW/WRN THEN SRN AK. SCHICHTEL