A stormy weather pattern midweek will help spawn powerful thunderstorms across parts of the Midwest and Ohio Valley.
The combination of warm and humid air will be fuel for thunderstorms to develop late on Tuesday along the I-80 corridor from central Iowa to northern Illinois.
Some of these storms will reach the Chicago area in time for the evening rush hour, and can contain cloud-to-ground lightning, strong winds and even hail.
The risk of locally severe storms will push to the southeast over portions of Indiana and Ohio later Tuesday night.
On Wednesday, conditions will come together to support strong-to-severe thunderstorms from the middle part of the Mississippi Valley through the Ohio Valley.
Storms on Wednesday into Wednesday night can contain damaging winds, large hail and flooding downpours.
St. Louis, Missouri, Indianapolis, Indiana, Louisville, Kentucky, Cincinnati, Ohio and Pittsburgh, Pennsylvania, could be directly affected by these intense thunderstorms.
Impacts could include slow travel and a higher risk of accidents on Interstates 70, 65, 57, 64, 74 and 71, along with flight delays at the major airports.
Power outages are also a threat due to lightning strikes and high winds pushing tree limbs onto power lines.
A drier and cooler pattern will set up during the latter portion of the week across the Midwest.
More at AccuWeather: St. Louis to Pittsburgh at Risk for Severe Storms