Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 345 PM EDT Wed Apr 27 2016 Valid 00Z Thu Apr 28 2016 - 00Z Sat Apr 30 2016 ...There is a slight risk of severe thunderstorms from the central Gulf Coast, Lower/Middle Mississippi Valley and parts of the Midwest through Thursday morning... ...Heavy rain possible for parts of the Western Ohio Valley today and portions of the Southern Plains on Friday... ...There is a slight risk of severe thunderstorms Thursday and Friday across portions of the Southern Plains... A strong line of showers and thunderstorms, with embedded severe storms, are moving through the Deep South ahead of an advancing cold front. An extensive swath of showers and thunderstorms are also present along and north of a quasi-stationary front spanning from the Midwest through the Ohio Valley and into the northern/central Appalachians. The western Ohio Valley has an increased threat for heavy rainfall as multiple storms track through. Flash flooding will be possible therefore an excessive rainfall outlook has been issued for much of Illinois, Indiana and Kentucky through Thursday morning. The showers and thunderstorms will span from Mid-Atlantic/Eastern Ohio Valley to the Southeast and parts of the Central Gulf Coast by Thursday as the low pressure system moves eastward - with rain over portions of the Central/Northern Plains and Great Lakes region. Higher elevation snow and lower elevation rain will develop over parts of the Northern High Plains and Central Rockies through Thursday morning. A second storm will move onshore the West Coast and move southeastward to the Desert Southwest/Southern Rockies by Thursday evening. The Pacific Northwest and northern California will have rain develop with this system. As the front moves inland, precipitation will spread into the Northern and Central Rockies. Snow will develop at the highest elevations, resulting in accumulations up to 1 foot across Colorado by Friday evening. Snow will decrease intensity through the day on Saturday as the system pushes further into the Southern Plains. Strong to severe thunderstorms will likely develop across portions of Oklahoma and Texas. The Storm Prediction Center has issued a slight risk for portions of the Southern Plains through early Saturday morning. Heavy rainfall may also accompany the convection of Friday, therefore an excessive rainfall outlook has been issued for nearly the same region. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php