ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 202 PM EST SUN DEC 11 2016 VALID 12Z THU DEC 15 2016 - 12Z MON DEC 19 2016 UPPER AIR PATTERN SUGGESTS THAT THE STRONG UPPER RIDGING IN PLACE OVER THE INTERIOR AT THE START OF THE MEDIUM RANGE PERIOD -- THURSDAY -- WILL BE CHIPPED AWAY FROM THE WEST BY A LEAD BERING SEA SYSTEM AND THEN AGAIN BY ANOTHER N PACIFIC SYSTEM EARLY NEXT WEEK. THOUGH USUALLY UPPER RIDGING STICKS AROUND LONGER THAN FORECAST BY THE MODELS/ENSEMBLES, TREND HAS BEEN DECIDEDLY TOWARD FLATTENING THE FLOW IN ABOUT A WEEK'S TIME. STILL, PREFER TO NOT RUSH THE RIDGE EROSION LIKE SOME DETERMINISTIC MODELS SHOW. CONSENSUS BLEND TO START -- 12Z GFS AND 00Z ECMWF/ECENS MEAN/GEFS MEAN -- SHIFTED THE BERING SEA LOW TO THE SOUTHEAST AND A BIT QUICKER THAN WHAT WAS FORECAST YESTERDAY. THEREAFTER, TRENDED TOWARD THE 00Z GEFS MEAN WHICH WAS SLOWER TO MOVE THE WEAKENING COLD FRONT EASTWARD INTO THE GULF AND THEN MORE DEFINED WITH THE NEXT SYSTEM MOVING THROUGH THE WESTERN ALEUTIANS THIS COMING WEEKEND. ECMWF ENSEMBLE MEAN APPEARED TOO WASHED OUT BETWEEN THE INCOMING SYSTEM AND THE OLD PARENT LOW IN THE BERING SEA TO THE NORTH. MODELS DIVERGE QUITE NOTICEABLY BY NEXT WEEKEND BUT FAVORED A SLOWER SOLUTION THAN THE 12Z GFS SINCE THE ENSEMBLE MEANS GENERALLY AGREE ON THAT. COLD AND DRY TO START, ESPECIALLY IN THE PANHANDLE, WILL BE REPLACED BY MILDER TEMPERATURES AND INCREASING POPS. WELL ABOVE AVERAGE TEMPERATURES SHOULD FLOW UP THROUGH WESTERN ALASKA AS SOUTHERLY FLOW AHEAD OF THE BERING SYSTEM ON THURSDAY TRANSPORTS MILD AIR INTO THE REGION. NEAR RECORD "WARM" TEMPERATURES MAY OCCUR, BOTH FOR DAYTIME HIGHS AND OVERNIGHT LOWS. ACTUAL TEMPERATURES MAY CLIMB INTO THE MID 30S OR OVER 40 IN THE BERING SEA. FRACASSO