A heat wave affecting areas from the Gulf Coast into the Midwest will ease in the latter region during the second half of the week.  However, hot, humid conditions will persist across the South.  During the weekend, extreme heat will again build northward across the nation’s mid-section, with high temperatures on Saturday, July 9, possibly exceeding 100°F as far north as South Dakota.  As the week progresses, hot weather will also return across much of the West. 

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