Across the Corn Belt, a cold front is producing showers and thunderstorms from the Great Lakes region into the middle Missouri Valley.  In advance of the front, Wednesday’s high temperatures should range from 90 to 100°F, accompanied by high humidity levels.  Meanwhile, slightly cooler air is overspreading the upper Midwest.  In parts of the Corn Belt, significant, short-term rainfall deficits have developed in recent weeks.  For example, rainfall in Des Moines, Iowa, totaled just 0.20 inch in the 27-day period from July 7 – August 2.

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