Cooler air will overspread the Northwest, while unusually hot weather will persist for much of the week in the nation’s mid-section, including the Plains and the western Corn Belt.  At times, 100-degree heat will reach as far north as Montana and the Dakotas, as well as parts of Iowa and southwestern Minnesota.  In contrast, temperatures will only briefly climb above 90°F in the eastern Corn Belt.  In addition, much of the eastern Corn Belt will have opportunities for rain, with 5-day totals reaching 1 to 2 inches or more. 

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