A zone of thunderstorms, centered over the Ohio Valley, can be locally strong and gusty Tuesday evening.
The storms bring the risk of frequent lightning strikes, locally gusty winds, hail and brief downpours that can cause urban flooding.
Cities in the path of the locally heavy, gusty storms include Louisville, Indianapolis, Evansville, Cincinnati, Dayton, Columbia, Youngstown and Pittsburgh, as well as Wheeling and Morgantown, W.Va.
The storms are being caused by a cool front sagging southward from the Upper Midwest.
The front is forecast by AccuWeather.com meteorologists to stall over the Ohio Valley later Tuesday night and Wednesday.
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Areas near and north of the front will be the focusing point for thundery rains through the end of the week, as a storm system rolls out of the Rockies.
Enough rain could fall from parts of Missouri to Iowa, Wisconsin, Michigan, Illinois, Ohio and Indiana to cause flash, urban and small stream flooding, as well as significant rises on some of the rivers.
The same storm will produce a swath of heavy snow on its northwestern flank and severe thunderstorms with the potential for tornadoes to the south and east.