Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 253 PM EST Tue Dec 24 2013 Valid 00Z Wed Dec 25 2013 - 00Z Fri Dec 27 2013 ...Snow is expected across the Great Lakes... ...Temperatures will be 10 to 15 degrees below average over the Northeast and Mid-Atlantic... Upper-level energy over Middle Mississippi Valley into South-Central Canada will move to the Lower Great Lakes/Ohio Valley by Thursday morning. The system will produce snow over parts of the Upper Mississippi Valley moving into the Great Lakes on Christmas, Wednesday, then into the Lower Great Lakes/Northeast by Thursday morning. Meanwhile, upper-level energy over the Lower Great Lakes will move quickly eastward out over the Gulf of Maine by afternoon on Christmas. The energy will trigger scattered snow over parts the Lower Great Lakes into parts of the Central Appalachians moving into parts of Southern New England by evening on Christmas. Elsewhere, easterly flow off the Atlantic will trigger scattered showers and thunderstorms over the southern tip of Florida through Thursday. Likewise, easterly flow off the Western Gulf of Mexico will trigger rain over parts of the Western Gulf Coast from Christmas evening into Thursday morning. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php