A significant pattern change will result in cool air overspreading much of the central and eastern U.S., with any lingering heat generally limited to the northern Plains and the Deep South.  Abundant showers will accompany the surge of cooler air into the South, where 5-day rainfall totals could reach 1 to 3 inches or more.  During the weekend, widespread rain may result in substantial drought relief across the southern Plains, including Oklahoma and northern Texas. 

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