EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1219 AM EST MON JAN 04 2016 VALID 12Z THU JAN 07 2016 - 12Z MON JAN 11 2016 ...OVERVIEW... STRONG RIDGING IS FORECAST TO HOLD THROUGH THE MEDIUM RANGE PERIOD IN THE HIGH LATITUDES NEAR BANKS ISLAND -- ABOUT A +2.5 STANDARDIZED ANOMALY -- WHICH FAVORS TROUGHING SHIFTING FROM THE WESTERN TO CENTRAL CONUS. THIS WILL TAKE THE STORM TRACK FROM THE SOUTHWESTERN STATES INTO THE CENTRAL PLAINS AND UPPER MIDWEST LATER THIS WEEK BEFORE A POTENTIAL COASTAL STORM OFF NEW ENGLAND BY THE END OF THE PERIOD. ...GUIDANCE EVALUATION/WPC PREFERENCES... FOR SEVERAL DAYS RUNNING, USED A BLEND OF THE RECENT GFS/GEFS AND ECMWF/ECENS MEAN GUIDANCE FOR THE BULK OF THE FORECAST. SYNOPTIC SCALE PATTERN HAS BEEN RELATIVELY WELL-FORECAST BUT LARGER MESOSCALE SHORTWAVES REMAIN A MOVING TARGET. 12Z/03 ECMWF FALLS ON THE WESTERN OR SOUTHWESTERN SIDE OF THE ENSEMBLE ENVELOPE WITH TROUGHING INTO MONTANA SAT/SUN AND ALSO WITH LOW PRESSURE IN THE SOUTHEAST -- FARTHER WEST THAN THE ENSEMBLE MEANS AND GFS/CANADIAN RUNS. EVOLUTION OF THE FLOW OVER/THROUGH CANADA HAS BEEN QUITE DIFFICULT TO RESOLVE IN THE MODELS/ENSEMBLES OVER THE LAST FEW DAYS, SO ALTHOUGH THE ECMWF WAS NOT INCLUDED IN THE BLEND THAT DOESN'T MEAN THAT IT'S AN 'OUTLIER' BUT RATHER A LOWER PROBABILITY SCENARIO. ...SENSIBLE WEATHER HIGHLIGHTS... THE OVERALL PATTERN FAVORS BELOW NORMAL TEMPERATURES ACROSS THE WESTERN HALF OF THE US WITH NEAR/ABOVE NORMAL TEMPERATURES IN THE EAST. DEVELOPING SURFACE LOW BY FRIDAY SHOULD LIFT INTO THE WESTERN GREAT LAKES BY SATURDAY WITH WINTRY PRECIPITATION ON ITS NORTH/NORTHWESTERN SIDE FROM NEBRASKA TO WISCONSIN AND MICHIGAN. THAT SYSTEM SHOULD WEAKEN AS IT MOVES INTO CANADA AS ANOTHER AREA OF LOW PRESSURE POSSIBLY FORMS ALONG THE FRONTAL BOUNDARY IN THE SOUTHEAST AND MOVES NORTHEASTWARD SUNDAY/MONDAY. OFFSHORE TRACK IS DEPICTED BUT AN INLAND RUNNER IS QUITE POSSIBLE. PRECIPITATION WILL OVERSPREAD THE EAST/NORTHEAST WITH P-TYPE TO BE DETERMINED BY TRACK -- IF THIS SYSTEM EVEN DEVELOPS AS MUCH AS FORECAST -- AS WELL AS COLD AIR IN PLACE. THIS WOULD FAVOR SNOW/MIX IN THE INTERIOR NORTHEAST AS TEMPERATURES ARE FORECAST TO STILL BE ABOVE NORMAL. FRACASSO