EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1244 AM EST SAT JAN 09 2016 VALID 12Z TUE JAN 12 2016 - 12Z SAT JAN 16 2016 ...GUIDANCE/UNCERTAINTY ASSESSMENT...WEATHER PATTERN HIGHLIGHTS AND THREATS... THE WPC MEDIUM RANGE PRODUCT SUITE WAS PRIMARILY DERIVED FROM A COMPOSITE BLEND OF REASONABLE WELL CLUSTERED GUDIANCE FROM THE 12 UTC GFS/ECMWF AND 12 UTC GEFS/NAEFS/ECMWF ENSEMBLE MEANS DAYS 3/4 TUE-WED. FOCUSED JUST ON THESE ENSEMBLES DAYS 5-7 CONSISTENT WITH INCREASING FORECAST SPREAD. THIS SOLUTION PROVIDES GOOD CONTINUITY. ENERGETIC FLOW ALOFT SPLITS OVER THE ERN PACIFIC WITH A NRN STREAM RIDING THE WRN PERIPHERY OF AN AMPLIFIED NW US/WRN CAN/INTERIOR AK MEAN RIDGE. A SERIES OF POTENT IMPULSES DIGGING TO THE LEE OF THE RIDGE PERIODICALLY REINFORCE A WINTERY EAST-CENTRAL CANADA/LOWER 48 MEAN TROUGH IN A PATTERN FAVORING SEVERAL LOWER LEVEL ARCTIC AIR INTRUSIONS. IN THIS FLOW A PROGRESSION OF MAINLY SNOW ORGANIZING CLIPPER LOWS WITH POST SYSTEM COOLING TO ENHANCE BOUTS OF GREAT LAKES EFFECT SNOWS. MEANWHILE...SRN STREAM PACIFIC ENERGY CUTS UNDERNEATH THE BLOCKY NRN LATITUDES IN SEPARATED FLOW INTO THE WETTENED WEST COAST AND INLAND ACROSS THE INTERMOUNTAIN WEST/SW US WITH MORE MODEST PCPN SWATHS. SYSTEMS SUBSEQUENTLY EJECTING OUT ACROSS THE US SRN/SERN TIER HAVE UNCERTAIN NRN STREAM FLOW/COLD AIR INTERACTIONS...BUT DO OFFER SOME WAVY FRONTAL RAINFALL POTENTIAL ALONG WITH SOME WINTERY SYSTEM/PCPN DEVELOPMENT THREAT TO MONITOR IN THE MARGINALLY COLD AIRMASS WELL OVERTOP LATER NEXT WEEK INTO NEXT WEEKEND AS LOWS AND OVERRUNNING MOISTURE FLOW EMERGES. SCHICHTEL