U.S. Postal Service letter carrier Monique Miller drinks from a bottle of water as she delivers mail in the Feltonville section of Philadelphia on Saturday July 7, 2012. Temperatures of more than 100 ... more 
U.S. Postal Service letter carrier Monique Miller drinks from a bottle of water as she delivers mail in the Feltonville section of Philadelphia on Saturday July 7, 2012. Temperatures of more than 100 degrees were forecast in Philadelphia and excessive heat warnings were issued for several states in the Midwest as a heat wave continued. (AP Photo/Joseph Kaczmarek) less 
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Associated Press | Photo By Joseph Kaczmarek
Sat, Jul 7, 2012 7:23 PM EDT