Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 323 PM EST Thu Nov 17 2016 Valid 00Z Fri Nov 18 2016 - 00Z Sun Nov 20 2016 ...Heavy snow possible from the Upper Mississippi Valley to parts of the Central Plains... ...Temperatures will be 10 to 25 degrees above average from the Great Lakes to the Lower Mississippi Valley and the Appalachians... ...Heavy rain over parts of Northern California... A storm over the Central Plains will move into Central Ontario by Saturday. Ahead of the associated front temperatures will be well above average for this time of year, while temperatures will become more seasonable behind the boundary. Snow will develop over parts of the Northern Plains and Central High Plains into the Northern/Central Rockies that will expand into parts of the Upper Mississippi Valley overnight Thursday and ending over the Northern/Central Rockies and High Plains by Friday morning. The snow will move out of the Northern/Central Plains by Friday evening while moving into the Upper Great Lakes/Middle Mississippi Valley Friday morning. Overnight Friday, the snow will move into parts of the Western Ohio Valley. In addition, rain will develop over parts of the Central Plains that will change over to snow by Friday afternoon. Rain will also develop over parts of the Upper Mississippi Valley/Upper Great Lakes overnight Thursday Furthermore, showers and thunderstorms will develop over parts of the Southern Plains by Friday morning that will expand into parts of the Lower/Middle Mississippi Valley by Friday afternoon and into parts of the Ohio Valley/Great Lakes by Friday evening. Overnight Friday, the showers and thunderstorms will become rain and rain showers. The rain will move to the Lower Great Lakes southward to the Central Gulf Coast by Saturday morning. Meanwhile, a front off the West Coast will move onshore over parts of the West Coast by Saturday morning. On Friday evening, a plume of moisture will move into parts of the Central/Northern California Coast producing areas of rain that will be heavy at times into Saturday morning. Rain will also develop over the Pacific Northwest overnight Friday into Saturday morning. Snow will develop over the highest elevations of the Cascades and Northern Sierras. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php