Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 249 PM EST Sun Feb 17 2019 Valid 00Z Mon Feb 18 2019 - 00Z Wed Feb 20 2019 ...Heavy rain possible over parts of the Lower Mississippi/Tennessee Valleys and parts of the Southern Appalachians... ...Heavy snow possible over parts of Lower Great Lakes into New England and over parts of the Southern/Central Rockies/Southwest... ...Temperatures will be 20 to 35 degrees below average over the Northern/Central Plains... A storm over the Ohio/Tennessee Valleys will move eastward off the Mid-Atlantic Coast by Monday morning. The system will produce snow over parts of the Great Lakes into parts of the Ohio Valley/Northern Mid-Atlantic that will move into New England overnight Sunday. The snow will begin to taper off from west to east over the Great Lakes into the Northeast Monday afternoon into early Tuesday morning. The system will also produce rain over the Ohio/Tennessee Valleys eastward to the Mid-Atlantic into the Southeast that will move off the coast by Monday evening. Additionally, an area of showers and thunderstorms will develop along and ahead of the associated front from parts of the Southeast to the Central Gulf Coast that will, likewise, move eastward into Southeast Coast and Florida by Monday. The showers and thunderstorms will linger over Florida through Tuesday. Along the rain/snow line there will be pockets of rain/freezing rain over parts of the Northern Mid-Atlantic through Monday morning. Meanwhile, a developing upper-level low over the Great Basin will move into parts of the Southwest by Tuesday morning continuing to move eastward into the Southern Rockies by Wednesday. The storm will produce snow over the interior higher elevation over the Pacific Northwest into California and snow over the Northern Intermountain Region into the Great Basin and the Northern/Central Rockies into parts of the Southwest. The snow will begin to taper off over the Pacific Northwest, California, and the Great Basin overnight Sunday. Rain along parts of the Pacific Northwest Coast and the California Coast will also taper off overnight Sunday. As the upper low moves into the Southwest, moisture from the Western Gulf of Mexico will start flowing northwestward into Southern Plains as the snow moves into parts of the Central Plains overnight Monday. On Tuesday, the snow will move into the Southern High Plains and into the Middle Mississippi Valley by Tuesday evening. Overnight Monday, showers and thunderstorms will develop over parts of the Western Gulf Coast into parts of the Southern Plains by Tuesday evening. Rain will develop over parts of the Southeast/Tennessee Valley into parts of the Southern Plains on Tuesday into Wednesday. Elsewhere, upper-level energy over the Northern High Plains into the Middle Mississippi Valley will aid in producing snow over parts of the area through Monday afternoon. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php