The combination of strong jet stream winds, strengthening low pressure and moisture returning northward from the Gulf of Mexico is setting the stage for a severe thunderstorm outbreak including a threat of damaging winds and some tornadoes this weekend.
Initially, a few severe storms may develop Saturday night from parts of eastern Iowa and northern Missouri to northwest Illinois. The main threats would be large hail and damaging winds, but there is also a low chance of a tornado.
However, it appears the greatest and most widespread threat of severe thunderstorms will be on Sunday. The red shading on the second map to the right illustrates that parts of the Great Lakes, Ohio Valley, lower/middle Mississippi Valley and Tennessee Valley are among the regions most at risk.
Source: The Weather Channel