Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 404 PM EDT Mon Oct 03 2016 Valid 00Z Tue Oct 04 2016 - 00Z Thu Oct 06 2016 ...There is a slight risk of severe thunderstorms over parts of the Northern/Central Plains and High Plains... ...Heavy rain possible over parts of the Upper/Middle Mississippi Valley... ...Heavy rain possible over parts of the Cascades... ...Temperatures will become 10 to 15 degrees below average over most of the Western third of the U. S.... A deep upper-level low over the Northern/Central Rockies will move northeastward and deepen over the Northern Plains by Wednesday. The system will produce showers and thunderstorms from parts of the Northern High Plains into the Northern/Central Plains southward into the Southern High Plains that will move into the Mississippi Valley by Wednesday. Rain will also develop over parts Northern/Central Rockies and into parts of the Great Basin continuing into Wednesday. In addition, heavy snow will develop over some of the highest elevations of the Northern and Central Rockies also through Wednesday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php