Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 252 PM EST Fri Nov 16 2018 Valid 00Z Sat Nov 17 2018 - 00Z Mon Nov 19 2018 ...Snow expected to increase across the upper Mississippi Valley and upper Great Lakes through tonight... ...Heavy snow possible across the northern and central Rockies... ...Air Stagnation and Air Quality Alerts continue to be in effect for parts of the Pacific Northwest and California... As the nor'easter that brought the wintry mix continues to move farther north into the Canadian maritimes, the light to moderate snow will decrease during the evening. By Saturday morning, the snow associated with this system will come to an end. However, another front will push across the upper and low Great Lakes tonight into Saturday. This will bring additional snowfall to the Great Lakes along with the New England interior--and will continue into Sunday. An Arctic high will slide into the northern tier states through the short term period. A cold front will make its way from the central Plains to the middle Mississippi Valley--ending up in the Mid-Atlantic by Sunday evening. With these ingredients along with forcing an upper level disturbance, a swath of snow from northeast South Dakota to western Michigan is expected. The heaviest snowfall expected in southern Minnesota, northeast Iowa, and southern Wisconsin. Most of this activity will occur on Saturday--ending by Saturday evening. Farther west, the same upper level disturbance and front impacting the Mississippi Valley and Great Lakes will also be impacting the Rockies. Heavy snow will continue across the northern Rockies through this evening. As the cold front, and Arctic high, move southward, the snowfall will also shift south into the central Plains. Lingering snow in the higher elevations of Colorado will be possible on Sunday morning--but will completely end by the afternoon. As the wildfires continue to burn across California and high pressure sits over the western U.S., air stagnation and air quality alerts will also persist through the weekend. These alerts are in effect for areas across the Pacific Northwest and central California. This high pressure will also lead to above normal temperatures across the western U.S. Meanwhile, the Arctic high will lead to temperatures nearly 25 degrees below normal throughout the Plains. Temperatures across the Ohio Valley and the East Coast will experience temperatures 5-10 degrees below normal. Reinhart Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php