Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 306 PM EST Sun Feb 18 2018 Valid 00Z Mon Feb 19 2018 - 00Z Wed Feb 21 2018 ...Heavy snow possible over the Northern Plains into the Central Rockies and the Upper Great Lakes... ...Heavy rain possible from parts of the Southern Plains northeastward to the Great Lakes... ...Rain/freezing rain possible over parts of the Middle/Upper Mississippi Valley into parts of the Upper Great Lakes... ...Temperatures will be 15 to 40 degrees below average over parts of the Northern/Central Plains into parts of the Northern Rockies... A front extending from the Upper Great Lakes to the Southern High Plains will become quasi-stationary through Tuesday. The system will produce snow over parts of the Upper Great Lakes/Upper Mississippi Valley into parts of the Northern Plains through Tuesday. The snow will expand into parts of the Central Plains on Monday into Tuesday. Moisture from the Western Gulf of Mexico will stream northward into parts of the Central/Southern Plains into parts of the Lower/Middle Mississippi Valley that will continue to flow northward into the Western Ohio Valley/Great Lakes on Monday into Tuesday. The moisture will aid in producing showers and thunderstorms over parts of the Southern Plains into parts of the Lower Mississippi Valley that will expand into parts of the Middle Mississippi Valley/Western Ohio Valley by Monday morning continuing through Tuesday. The moisture will also produce rain over parts of the Southeast that will lift northward into the Ohio Valley/Mid-Atlantic by Monday morning. The rain will continue to move northward into parts of the Northeast by Monday evening into Tuesday. Additionally along the rain/snow line, rain and freezing rain will develop over parts of the Central Plains into parts of the Upper Great Lakes Monday morning into Tuesday. Meanwhile along the western parts of the storm, the western end of the front will extend from the Central Rockies into the Great Basin and Southern California. The boundary moves eastward to the Southern High Plains by Tuesday. The system produces snow from parts of the Pacific Northwest/Northern California eastward to the Northern/Central High Plains and coastal rain over parts of the Northern/Central California Coast that will move southeastward into the Great Basin/Central Rockies overnight Sunday into Monday. The snow will continue to move southeastward into parts of the Southwest/Southern Rockies and the higher elevations of Central/Southern California by Monday evening. The snow will wane over parts of the Pacific Northwest/Northern Rockies and parts of California/Great Basin/Southwest by Tuesday. In addition, overnight Sunday rain will develop over parts of the Southwest and Southern California Coast with rain ending over parts of Southern California Coast by Monday evening. The rain over the Southwest will change over to snow overnight Monday into Tuesday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php