Next weekend, extreme heat will make another westward shift, allowing cooler air to overspread the Midwest.  Hot weather will linger, however, in the Deep South.  As heat builds northward through the western U.S., melting of high-elevation snow could result in elevated Northwestern river levels.  Meanwhile, widespread precipitation will be scarce during the next several days, except in the southern Rockies, where monsoon-related thunderstorms could spark flash flooding.  The Midwest will receive scattered, late-week thunderstorms, but mostly dry weather will prevail in the Southeast and Far West. 

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