ALASKA EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 226 PM EDT MON APR 11 2016 VALID 12Z FRI APR 15 2016 - 12Z TUE APR 19 2016 AMPLIFIED BUT PROGRESSIVE PATTERN TO CONTINUE FOR AT LEAST THE NEXT WEEK. GENERALLY THE ECMWF/ECENS MEAN HAVE BEEN PREFERRED BUT HAVE TENDED TO TREND A BIT QUICKER WITH EACH RUN. GFS/GEFS OFTEN HAVE BEEN QUICKER, WHICH IS BETTER, BUT NOT NECESSARILY IN THE RIGHT PLACE OR ALONG THE CORRECT TRACK. DIFFERENCES BETWEEN THE GFS/GEFS AND ECMWF/ECENS CAMPS WERE BELOW THE TYPICAL SPREAD BUT OPTED TO RELY MORE ON THE ECMWF/ECENS BLEND WITH SOME GEFS INFLUENCE VIA THE NAEFS MEAN. LEAD SYSTEM IN THE GULF FRIDAY WILL WEAKEN INLAND BUT TRAILING/DEVELOPING SFC WAVE WILL PUSH NORTHEASTWARD SAT/SUN INTO SE AK. MODELS INDICATE A MUCH QUICKER PROGRESSION COMPARED TO 24 HRS AGO, BUT THOUGHT THE ECMWF WAS A BIT TOO QUICK ESPECIALLY ALOFT. ECENS MEAN OFFERED A MORE REASONABLE EVOLUTION (LIKE THE 00Z GEFS MEAN). IN THE BERING, THE ENSEMBLES STILL INDICATE A RESPECTABLY DEEP SYSTEM TO TRAVEL EASTWARD NORTH OF THE ALEUTIANS SAT-MON. RECENT GFS RUNS WERE FARTHER SOUTH ALONG OR JUST SOUTH OF THE ISLAND CHAIN BUT THAT DEPARTS FROM THE GREATER CONSENSUS NEAR THE ECMWF AND ENSEMBLE MEANS. THAT SYSTEM SHOULD PROGRESS EASTWARD AND WEAKEN AS YET ANOTHER SYSTEM ENTERS THE BERING OR WESTERN ALEUTIANS NEXT MON INTO TUE. ENSEMBLES SHOWED EXCELLENT AGREEMENT ON THIS SYSTEM, EVEN AT 8 DAYS OUT, BUT THAT DOES NOT MEAN IT WILL REMAIN THAT WAY. UPPER HIGH IN THE ARCTIC SHOULD REMAIN THERE THROUGH THE PERIOD, LEAVING ROOM FOR A WEAKNESS ALONG THE NORTH SLOPE THAT SHOULD CONTINUE TO SLIDE WESTWARD UNDER THE HIGH. FRACASSO