After an extended drought period, Lake Powell, which is in Utah and Arizona, reached drastically low levels last summer, but levels began rising in earnest in April after California experienced a wet winter. The above-average snowfall in the mountains led to an increased snowpack melt that has continued to supplement Lake Powell, as well as Lake Mead in Arizona and Nevada, this summer. However, a heat wave bringing triple-digit temperatures and dry weather to the Southwest could douse hopes that the lakes are recovering. … A decrease in levels is typical in the summer months as snowpack melt stops and the region enters a dry period, and a heat wave may exacerbate the lake’s tendency to lose water during summer months, according to AccuWeather senior meteorologist David Houk.

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