ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1230 PM EST THU DEC 11 2014 VALID 12Z MON DEC 15 2014 - 12Z FRI DEC 19 2014 ...AN ACTIVE WEATHER PATTERN UP INTO ALASKA... THE LATEST MODELS AND ENSEMBLES OFFER A REASONABLY SIMILAR LARGER SCALE MEDIUM RANGE FLOW EVOLUTION THAT OFFERS AVERAGE OR BETTER FORECAST CONFIDENCE AND CONTINUITY. THIS FLOW IS HIGHLIGHTED ALOFT BY AN UNSETTLING MEAN BERING SEA TROUGH THAT WEAKENS OVER TIME...AMPLE LEAD LOW ENERGIES CUTTING ACROSS THE GULF OF ALASKA AND SPREADING HEAVIER PCPN/WINDS INTO SRN/SERN AK UNDERNEATH GENERALLY BENIGN AND MODERATING WRN CANADIAN TO ALASKAN INTERIOR MEAN RIDGING...AND SUBSEQUENT UPSTREAM DEEP LOW DEVELOPMENT AND WEATHER/WAVES OUT FROM THE N-CENTRAL PACIFIC TOWARD THE ALEUTIANS AND VICINITY IN ABOUT A WEEK OR SO. THE DETERMINISTIC MODELS CHARACTERISTICALLY DIFFER MORE SIGNIFICANTLY WITH LESS PREDICTABLE EMBEDDED AND LOCAL WEATHER FOCUSING SMALLER SCALE EMBEDDED FEATURES. THIS SUGGESTS PREFERENCE FOR AN ENSEMBLE MEAN FORECAST APPROACH AND THE 00 UTC ECMWF/NAEFS MEANS SEEM WELL CLUSTERED. BLENDED THESE GUIDANCE OPTIONS FOR PRIMARY DERIVATION OF THE WPC ALASKAN SURFACE FRONTS/PRESSURES AND 500 MB PROGS ALONG WITH ASSOCIATED SENSIBLE WEATHER GRIDS. LEANED A BIT HEAVIER ON THE ECMWF ENSEMBLE MEAN THAT MAINTAINS SLIGHTLY BETTER WPC CONTINUITY. SCHICHTEL