Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 413 AM EDT Fri May 20 2016 Valid 12Z Fri May 20 2016 - 12Z Sun May 22 2016 ...Heavy rain possible over parts of the Ohio Valley and parts of the Southern Mid-Atlantic... ...Temperatures will be 10 to 15 degrees below average from parts of the Central Plains to the Ohio Valley and Southern Mid-Atlantic/Southeast... ...Temperatures will be 10 to 20 degrees below average over California/Great Basin into the Northern Intermountain Region... Upper-level energy over the Middle Mississippi Valley will move eastward to the Eastern Ohio Valley/Mid-Atlantic and merge with energy moving southward out of Central Canada by Saturday evening. Showers and thunderstorms will develop over parts of the Middle/Lower Mississippi Valley into parts of the Tennessee Valley/Southeast that will move eastward to the Mid-Atlantic/Southeast by Saturday morning. Rain will develop over parts of the Northern Mid-Atlantic on Saturday morning expanding into parts of Southern New England by Saturday evening. Showers and thunderstorms will continue over parts of the Eastern Ohio Valley/Central Appalachians and parts of the Mid-Atlantic/Southeast Coast on Saturday evening, too. Meanwhile, another upper-level low over the Pacific Northwest/Northern California will be quasi-stationary over the West Coast through Saturday evening. Rain and highest elevation snow will develop over parts of Northern California to parts of the Northern/Central Rockies on Friday morning through to Saturday evening. Rain will develop over parts of the Pacific Northwest on Friday afternoon into Friday evening continuing through Saturday evening. On Friday evening, showers and thunderstorms will develop over parts of the Northern/Central Rockies and the Northern/Central High Plains that will continue over parts of the region through Saturday evening. In addition, moisture from the Western Gulf of Mexico will move northward over parts of the Southern Plains on Saturday morning and move farther north into parts of the Central Plains by Saturday evening. The moisture will aid in producing showers and thunderstorms over parts of the Western Gulf Coast on Saturday morning that will expand over parts of the Southern/Central Plains by Saturday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php