Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 349 AM EDT Thu May 16 2019 Valid 12Z Thu May 16 2019 - 12Z Sat May 18 2019 ...There is a slight risk of severe thunderstorms from parts of the Central Plains to the Great Lakes/Western Ohio Valley... ...Heavy snow over the Sierra Nevada... ...Heavy rain possible over parts of Northern California, parts of the Central Plains into the Middle Mississippi Valley, and parts of the Southern Plains... ...Temperatures will be 10 to 25 degrees above average over the parts of the Central Plains... A front over the Upper Great Lakes/Upper Mississippi Valley that extends roughly westward across the Northern Plains/Northern Rockies into the Great Basin will move eastward to the Northeast by Friday evening. The boundary will move off the Northeast Coast by Saturday with the trailing front extending westward to the Central Plains. Showers and thunderstorms will develop along and ahead of the boundary over parts of the Upper Mississippi Valley/Upper Great Lakes that will move into the Great Lakes by Thursday evening, moving into the Northeast by Friday morning. The showers and thunderstorms will move off the Northeast Coast overnight Friday. In addition, showers and thunderstorms will continue along the front from the Great Lakes/Ohio Valley westward into the Middle Mississippi Valley/Central Plains Thursday into Saturday. Ahead of the Upper Midwest system, a weak front extends from Southern New England/Northern Mid-Atlantic into the Great Lakes will move off the Northeast Coast by Thursday evening. The system will produce scattered rain over parts of Southern New England into the Northern Mid-Atlantic, likewise, moving off the coast by Thursday evening. Meanwhile, another front over California/Great Basin will move eastward to the Central/Southern High Plains by Friday evening. The storm will produce rain over parts of California, Pacific Northwest, and the Northern Rockies that will spread eastward into the Eastern Great Basin and Northern High Plains by Thursday evening. Additionally, snow will develop over the Sierra Nevada and over the higher elevations of the Great Basin into parts of the Northern Rockies through Friday evening. The snow will end over the Sierra Nevada overnight Friday. Rain with embedded thunderstorms will develop over parts of the Northern/Central Rockies that will wane overnight and re-fire during the day on Friday and wane again by Friday night. Overnight Thursday, a strong plume of moisture will move northward over the Southern High Plains that will extend northward to the Central Plains into Saturday. A dryline will develop over the Central/Southern High Plains on Thursday night into Saturday. Showers and thunderstorms will develop east of the dryline on Friday becoming more numerous overnight Friday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php