Both excessive heat and more humidity returned to most of Eastern Pennsylvania starting on Independence Day and lasted until the 7th. The excessive heat claimed the lives of eight people, five within Philadelphia and three in Lehigh County.
High temperatures on the 2nd and 3rd were between 90 and 95 degrees in most places, but humidity levels were relatively low.  High temperatures on the  4th reached the mid 90s and combined with more humidity produced afternoon hourly heat indices of near 100F.  High temperatures on the 5th and 6th were in the mid to upper 90s, with similar afternoon heat indices. The heat and humidity peaked on the 7th with high temperatures around 100F and afternoon hourly heat indices between 102F and 108F. A cold front slipped south through the area on the evening and overnight on the 7th. Coupled with more cloudiness, high temperatures were in the lower 90s on the 8th and below 90F in most places on the 9th.
In Philadelphia, five people between the ages of 53 and 80 succumbed from the heat. In Allentown (Lehigh County), an 86-year-old man died of hyperthermia on the 7th. While there was an air conditioner, it was not operating. The temperature inside the house was more than 90 degrees when the body was discovered.  In Weisenberg Township, a 90-year-old husband and wife both died from the heat. The air-conditioner also was not operating and the temperature within the house was over 100 degrees.
To combat the heat, many counties, cities and municipalities opened cooling centers. The hours of air-conditioned senior citizen centers were extended. In Philadelphia, the Corporation for Aging had councilors and nurses on the phone.  In Philadelphia, an outdoor concert in Manayunk scheduled for the 7th was cancelled. The horse racing card at Parkx in Bensalem (Bucks County) was also cancelled on the 7th.
Highest temperatures all occurred on the 7th and included 103F in Reading (Berks County), 101 degrees in Philadelphia (the third consecutive summer that the high temperature reached 100 degrees in Philadelphia), 100 degrees in Pottstown (Montgomery County) and Doylestown (Bucks County), 99 degrees at the Lehigh Valley International Airport and Quakertown (Bucks County) and 98 degrees in West Chester (Chester County).
The string of 12 consecutive days of high temperatures reaching 90 degrees or higher in Philadelphia that ended on July 9th was tied for the 4th longest on record dating back to 1874. It was the longest stretch since the summer of 1999 which also had a string of 12 consecutive days. The string of 11 consecutive days of high temperatures reaching 90 degrees or higher in Reading (Berks County) that ended on July 8th was tied for the 3rd longest on record dating back to 1898. It matched a similar string last summer.

Heat in LEHIGH, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 17:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heat in NORTHAMPTON, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 17:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in BERKS, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 17:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in CHESTER, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Excessive Heat in MONTGOMERY, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in BUCKS, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in DELAWARE, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in PHILADELPHIA, PENNSYLVANIA
From 04-JUL-12 11:00:00 to 07-JUL-12 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS