ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 219 PM EDT THU MAY 29 2014 VALID 12Z MON JUN 02 2014 - 12Z FRI JUN 06 2014 UPPER-LEVEL TROUGHING AND RELATIVELY LIGHT FLOW ALOFT SHOULD PREVAIL DURING THE DAY 4-5 PERIOD...AND THE LATTER HALF OF THE ALASKAN MEDIUM RANGE FORECAST PERIOD (DAY 6-8) WILL BE CHARACTERIZED BY A NORTHERLY FLOW ALOFT---AN ACCELERATION OF THE FLOW SUPPORTING A SHARP UPPER-LEVEL RIDGE OVER THE BERING SEA/WESTERN INTERIOR AND WEAK TROUGHING WITH WEST-TO-SOUTHWEST FLOW IN THE SOUTHERN GULF OF ALASKA. (THIS FLOW PATTERN TRANSITIONS FOR NORTHWEST TO SOUTHEAST) MUCH OF THE 'RESHUFFLING' OF THE PATTERN IN THE LOWER LEVELS LOOKED TO BE OVER THE MID-LATITUDE PACIFIC...AND DOWNSTREAM OVER THE WEST CENTRAL COAST OF THE MAINLAND. THOUGHT THE 29/00Z ECENS AND GEFS MEANS WERE A REASONABLE COMPROMISE WITH THE GEFS--A TAD FASTER...THE ECENS---A TAD SLOWER. THOSE DIFFERENCES CROP UP IN THEIR DETERMINISTIC RUNS...BUT BOTH RUNS SUPPORT SOME SURFACE REFLECTION IN THE SOUTHERN GULF OF ALASKA AFTER DAY 5. THIS WEAK WAVE...BEING CARRIED DOWNSTREAM BY THE UPPER-LEVEL TROUGH CARVING OUT OVER THE PANHANDLE AND EVENTUALLY DOWNSTREAM INTO BRITISH COLUMBIA...WILL LIKELY BECOME THE 'PLACEHOLDER' FOR ONSHORE PACIFIC LOW-LEVEL FLOW AND FUTURE LOW-LEVEL WAVE DEVELOPMENT WITHIN THE GULF OF ALASKA. FOR THIS PACKAGE...THE ECENS/GEFS GENERALLY SUPPORT A RATHER BENIGN SENSIBLE WEATHER PATTERN FOR THE COASTAL SECTIONS OF THE GULF...AND MILD TO SEASONAL PATTERN FOR MUCH OF THE INTERIOR. VOJTESAK