ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 310 PM EST THU DEC 15 2016 VALID 12Z MON DEC 19 2016 - 12Z FRI DEC 23 2016 ...PATTERN OVERVIEW...GUIDANCE/UNCERTAINTY ASSESSMENTS...AND WEATHER HIGHLIGHTS... AN AMPLIFIED MID-UPPER LEVEL RIDGE NOW OVER THE STATE IS EXPECTED TO BE NUDGED EASTWARD ACROSS ERN/SERN AK INTO WRN CANADA BY EARLY NEXT WEEK AS APPROACHING ARCTIC STREAM TROUGH ENERGIES AND BERING SEA/NERN PACIFIC SYSTEMS/HEIGHT FALLS PROGRESS FORWARD. THIS WILL CONTINUE TO MODIFY THE RECENT COLD HIGH PATTERN DOWN OVER THE INTERIOR. FARTHER SOUTH...THE TWO MOST RECENT GFS/ECMWF RUNS AND ENSEMBLE TRENDS NOW HOLD MORE ASSOCIATED AND HIGHLY DEEPENED SURFACE LOW EMPHASIS LONGER OVER THE SERN BERING SEA THAN YESTERDAYS CONTINUITY THAT WAS QUICKER TO TRANSFER ENERGIES AND EMERGE POTENT LOWS DOWNSTREAM INTO THE STILL ACTIVE NRN GULF. THE WPC PRODUCT SUITE MODESTLY FOLLOWS THIS TREND CONSIDERING LEAD RIDGE AMPLITUDE ALOFT. FORECAST PREDICTABILITY HAS PROVEN TO BE LESS THAN STELLAR WITH SPECIFICS AS EVIDENCED BY THE LATEST GUIDANCE RUN TO RUN VARIANCE/JUMPINESS. THIS LENDS A GEFS/NAEFS/ECMWF BLENDED ENSEMBLE FORECAST APPROACH. IN ANY CASE HOWEVER...THE PATTERN SHOULD PROVE PERIODICALLY WET AND HIGHLY UNSETTLED FROM WRN AK AND THE ALEUTIANS/SW AK TO SRN AND SERN AK...ESPECIALLY OVER FAVORED COASTAL TERRAIN...WITH THESE HIGH PCPN/WIND/WAVES FOCUSING SERIES OF STORMS ALL NEXT WEEK. SCHICHTEL