Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 316 PM EDT Mon May 18 2015 Valid 00Z Tue May 19 2015 - 00Z Thu May 21 2015 ...There is a slight risk of severe thunderstorms for parts of the Southern High Plains... ...Heavy rain possible over parts of the Southern Plains... ...Heavy rain possible over parts of the Central High Plains... ...Temperatures will be 15 to 30 degrees below average over parts of the Central High Plains/Central Rockies... A front extending from the Great Lakes southwestward to the Southern High Plains will move eastward to off the Northeast/Mid-Atlantic Coast then westward across the Southeast to the Southern High Plains by Wednesday morning. Moisture pooling along the boundary will aid in producing showers and thunderstorms from the Northeast roughly southwestward to the Lower Mississippi Valley/Eastern Gulf Coast that will move eastward off the Northeast/Mid-Atlantic Coast by Wednesday. Showers and thunderstorms will remain over the Southeast to the Southern Plains through Wednesday morning. In addition, rain will develop ahead of the front over parts of the Northeast Tuesday morning into late Tuesday evening. A second area of rain over the Upper Great Lakes will move eastward to parts of Northern New England by Wednesday morning. Meanwhile, upper-level energy over Central California will move northeastward to the Central High Plains by Wednesday. The energy will also induce a low over the Southern High Plains by Tuesday afternoon that will move eastward to the Southern Plains by Wednesday morning. The upper-level low will aid in producing rain with embedded thunderstorms from parts of the Pacific Northwest roughly southeastward to the Central/Southern Rockies through Wednesday. As the energy moves eastward, moisture from the Western Gulf of Mexico will stream northward over the Southern/Central Plains into parts of the Lower/Middle Mississippi Valley Tuesday into Wednesday. Showers and thunderstorms will develop over the Southern High Plains and move eastward into the Southern Plains/Lower Mississippi Valley by Wednesday. Rain will also develop over parts of the Central High Plains and move eastward to the Middle Mississippi Valley by Wednesday morning. Some of the highest elevations of the Rockies will have wet snow through Wednesday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php