Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 300 AM EST Sat Jan 23 2021 Valid 12Z Sat Jan 23 2021 - 12Z Mon Jan 25 2021 ...Snow for the Great Basin, Central/Southern Rockies, and the Southwest through Sunday... ...Heavy lake-effect snow expected downwind of the Great Lakes through Saturday morning... ...Snow for the Upper/Middle Mississippi Valley on into Sunday... ...Moderate to Heavy rainfall possible from the Southern Plains to the Tennessee Valley Sunday and Monday... The West and the Plains will have active weather through the weekend into early next week as a low pressure system tracks across the Great Basin, Rockies and exits into the Plains. Snow will be fairly scattered to widespread, spanning from the Great Basin to the Northern High Plains, and to points south near the Four Corners region while parts of California and the Southwest get some rain. A secondary round of precipitation, rain in the lower elevations and mountain snow, is expected for Sunday. Some locations may receive several inches of locally heavy snow, which may lead to hazardous travel conditions for the Southwest and Southern/Central Rockies region. This system will exit into the Plains by late Sunday and track east through the Lower Mississippi Valley. Moderate to heavy rainfall is expected to develop along and ahead of the frontal boundary, which may lead to an elevated threat for excessive rainfall and flash flooding conditions. WPC has identified portions of the Southern Plains, Lower/Mid-Mississippi and western Tennessee Valleys are having a Marginal Risk for. Across the Upper Midwest and Great Lakes region, Canadian high pressure will slide south keeping the air much cooler into early next week. With a slow moving cold front in present across the region, areas downwind of the Lakes Erie and Ontario will have continuing heavy lake-effect snow through mid-morning before tapering off by Saturday afternoon. In the meantime, a front will begin to move onshore over the Pacific Northwest Sunday morning, moving inland to parts of the Great Basin by Sunday evening. Coastal rain and higher elevation snow across Washington and Oregon is expected with this system and will then expand into Northern California Sunday afternoon and evening. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php