Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 414 PM EDT Sun May 15 2016 Valid 00Z Mon May 16 2016 - 00Z Wed May 18 2016 ...There is a slight risk of severe thunderstorms over parts of the Southern High Plains... ...Heavy rain possible over the Central Plains into the Middle Mississippi Valley and parts of the Western Gulf Coast... ...Temperatures will be 10 to 20 degrees below average from the Central Appalachians westward to the Central Rockies... An upper-level low over the Northern Intermountain Region will slowly sink southward to the Great Basin by Tuesday. Rain will develop over parts of the Pacific Northwest through Monday evening. The system will also produce showers and thunderstorms over parts of the Northern Intermountain Region southeastward to parts of the Western Gulf Coast on Sunday evening. Overnight Sunday, the showers and thunderstorms will expand into parts of the Central/Southern Plains and into parts of the Middle/Lower Mississippi Valley and expand into parts of the Western Ohio Valley overnight Monday. Additionally, showers and thunderstorms will develop over parts of the Southeast by Tuesday morning. On the other hand, the showers and thunderstorms will end over parts of the Northern Intermountain Region/Rockies by Monday morning, too. Also on Monday night, the showers and thunderstorms will begin to taper off over the Western/Central Gulf Coast. Rain will also develop over parts of the Southern Ohio Valley eastward to parts of the Mid-Atlantic on Monday night into Tuesday. Meanwhile, a second upper-level low over the Northeast will move eastward into Eastern Canada by Tuesday. Rain showers will develop over parts of the Northeast that will diminish to Northern New England by Monday morning and end over Maine by Tuesday morning. In addition, a weak system over South-Central Canada will move southeastward to the Lower Great Lakes by Tuesday morning. The storm will produce rain over parts of the Upper Mississippi Valley/Upper Great Lakes on Sunday evening that will move southeastward and expand into parts of the Middle Missouri Valley to parts of the Lower Great Lakes by Monday evening. The rain will be limited to parts of the Lower Great Lakes/Northern Ohio Valley by Tuesday morning. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php