Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 300 AM EST Wed Dec 07 2016 Valid 12Z Wed Dec 07 2016 - 12Z Fri Dec 09 2016 ...Heavy snow possible over the Sierras... ...Heavy snow possible in downwind favored areas from the Great Lakes... ...Rain/freezing rain possible over interior portions of the Pacific Northwest/Northern California... ...Temperatures will be 15 to 35 degrees below average over the Northern/Central Rockies and High Plains... Deep low pressure just north of the Great Lakes will slowly move northeastward to just east of James Bay by Thursday evening. The associated upper-level low will pass just north of the Keweenaw Peninsula on Wednesday will aid in producing the heaviest snow over the Great Lakes. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php