Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 310 PM EST Thu Nov 21 2013 Valid 00Z Fri Nov 22 2013 - 00Z Sun Nov 24 2013 ...Snow for the Upper Great Lakes... ...Heavy snow for Central Rockies... ...Heavy rain for the Southern Plains/Lower Mississippi Valley and the Southwest... ...Temperatures will be 10 to 30 degrees below average over Central/Southern High Plains... A slow moving strong front extending from the Great Lakes\Southern Plains to the Central Rockies will move eastward off the Northeast Coast to the Carolinas/Gulf Coast into Mexico by Saturday. Rain will develop over Great Lakes/Ohio Valley and the Middle Mississippi Valley will, likewise, move off the Northeast Coast and move into the Southeast. Showers and thunderstorms will develop along and ahead of the boundary over the Southern Plains/Lower Mississippi Valley retreating to the Western/Central Gulf Coast by Saturday. Rain will develop behind the front over the Southern Plains into the Lower Mississippi Valley and interior Central Gulf Coast on Friday into Saturday. As cold air settles over the Plains, sleet will develop over parts of the Southern High Plains also from Friday to Saturday. On the backside of the northern half of the precipitation shield, snow will develop over parts of the Middle Mississippi Valley into the Great Lakes Thursday evening into Friday evening. A developing upper-level closed low over Southwestern California will aid in producing snow over the Great Basin into the Central Rockies through Saturday. Snow will develop over the Southern Rockies by Saturday morning. Rain will develop over parts of Southern California into the Southwest with an area of light to moderate rain developing over the Southwest Friday into Saturday. Another front over South-Central Canada will move southeastward into the Great Lakes/Middle Mississippi Valley Friday morning into Saturday morning. The system will produce snow over parts of the Northern Rockies into the Great Lakes by Saturday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php