A severe weather outbreak will unfold across the central and southern Plains, with expectations of multiple, long-track tornadoes and hail up to 2 to 4 inches in diameter, especially in parts of Oklahoma and southern Kansas.  Strong thunderstorms may occur as far north as the northern Plains and eastward into the middle Mississippi Valley.  Subsequently, the threat of severe weather will slightly diminish and shift eastward, reaching the mid-South and Ohio Valley by the middle of the week. 

…