Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 406 PM EDT Tue May 12 2015 Valid 00Z Wed May 13 2015 - 00Z Fri May 15 2015 ...Heavy rain possible over parts of the Southern Plains... ...Temperatures will be 10 to 15 degrees below average over parts of the Southern Plains and over parts of the Great Lakes to the Upper Mississippi Valley.. A front extending from the East Coast to the Gulf of Mexico will move eastward out over the Western Atlantic and dissipate over the Gulf Coast by Wednesday evening. Showers and thunderstorms will develop along parts of the Gulf Coast through Wednesday morning. Light rain will also develop over parts of New England and extend westward into the Upper Great Lakes by Tuesday evening ending by Wednesday afternoon. Meanwhile, upper-level low over the Pacific Northwest will spin over the area as additional upper-level energy reinforces the low on Wednesday into Thursday morning. Rain will develop along the Northwest Coast and slowly move southward into parts of Northern California/Great Basin by Thursday. Afternoon and evening showers and thunderstorms will develop over parts of the Northern Rockies/Great Basin on Tuesday and Wednesday. Overnight Tuesday into Wednesday morning, rain will develop over parts of the Northern Plains. Upper-level energy rounding the base of the upper-level trough over Northwestern Mexico will move northeastward to Central Plains by Thursday morning. Concurrently, moisture from the Western Gulf of Mexico will move northward over the Plains. The moisture will also aid in the development of showers and thunderstorms over the Southern/Central Rockies by Tuesday evening. The showers and thunderstorms will move out over the Southern Plains by Wednesday morning and move eastward to the Western Gulf Coast by Thursday morning. Rain will also develop over parts of the Southern/Central Rockies on Wednesday morning that will move northeastward out over parts of the Central/Southern Plains by Wednesday evening and into parts of the Upper/Middle Mississippi Valley by Thursday morning. In addition, rain will develop over parts of the Northern Plains into the Upper Mississippi Valley with embedded thunderstorms also by Thursday morning. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php