Mount Lebanon, Pennsylvania, July 17, 2008—Six-year-old Joe Eisley cools off with a garden hose outside his home in a Pittsburgh suburb. The day marked the start of a four-day regional heat wave, with temperatures pushing into the 90s (Fahrenheit).

Some senior centers stayed open longer to offer air-conditioned respite to elderly residents. Meanwhile, officials in four mid-Atlantic states agreed to increase flows from a chilly Catskill reservoir into the Delaware River during hot spells to protect fish.

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