Heat currently in place across much of the southern and western U.S. will gradually expand across the nation’s midsection, with weekend temperatures topping 100°F as far north as eastern Montana.  Early next week, unfavorably hot weather will shift further eastward into portions of the western Corn Belt.  At that time, cool weather will be mostly limited to the Pacific Northwest and the Great Lakes and Northeastern States.  Meanwhile, a drier weather pattern will accompany the building heat. 

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