Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 300 PM EST Sat Nov 18 2017 Valid 00Z Sun Nov 19 2017 - 00Z Tue Nov 21 2017 ...Heavy precipitation possible over parts of the Northwest, Ohio Valley, Lower Great Lakes, and Northeast... A complex low pressure system moving through the Ohio Valley today will continue to lift through the Northeast this evening and on Sunday. It will spread heavy precipitation to portions of the Northeast. In its wake, Lake Effect snows are expected downwind of the Great Lakes within the main zone of its associated cold advection. Strong surface high pressure will expand from the Great Basin into portions of the Southwest/Southern Plains. Warm and dry conditions are expected across most of the Southwest and Southern/Central Plains. Elevated fire weather risk will continue per the Storm Prediction Center. Across the Pacific Northwest, onshore flow ramps up as a cold front approaches the region which should lead to heavy rains and higher elevation snows as the front moves into the area. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php