Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 349 PM EDT Wed Oct 23 2013 Valid 00Z Thu Oct 24 2013 - 00Z Sat Oct 26 2013 ...Lake effect rain and snow showers downwind from the Great Lakes... ...Temperatures will be 10 to 15 degrees below average over the Ohio/Middle Mississippi Valleys... A deep upper-level low over Southeastern Canada will spin over most of Eastern North America, while impulses of energy flow over the Great Lakes/Ohio Valley. The upper-level energy embedded in the broad counter-clockwise flow will trigger lake effect snow and rain showers downwind from the Great Lakes into parts of the Central/Northern Appalachians through Friday. In addition, an old front just off the Southern Florida Coast will aid in producing showers and thunderstorms over the southern tip of Florida through Thursday evening. A weak front over the Southern Plains will move eastward to off the Southeast Coast. The associated upper-level energy will produce light rain over parts of the Middle Mississippi Valley moving into the Central Appalachians by Thursday afternoon. Additionally, a weak upper-level low over Southern California will move eastward to the Southwest/Great Basin by Friday morning developing scattered showers and thunderstorms over parts of the Southern Rockies Thursday evening into Friday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php