Midwestern heat will peak Friday, with maximum temperatures topping 100°F as far north as Minnesota and as far east as the middle Mississippi Valley.  Eastern temperatures will approach or reach 100°F as far north as the mid-Atlantic.  During the weekend, cooler air will overspread the Midwest, excluding the southern tier of the Corn Belt.  Hot, humid conditions will linger, however, across the South.  By early next week, heat will re-intensify across the central Plains and southwestern Corn Belt, with 100-degree temperatures extending into Kansas and Missouri. 

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