Tracey Branch of West Philadelphia found a shady spot to enjoy a free Wawa hoagie with her mother.
"Just enjoying a day of people. Getting to know everybody who's all around," Branch said.
Despite the high temperatures, she remained upbeat.
"The heat is frying me, but it's a cool breeze blowing, they got the fans going, we got our waters out, we're doing good. We're enjoying music, everything is good," she said.
Crowds lined up around Independence Mall to receive what organizers described as 30,000 free hoagies during the annual event.
Attendees sought relief from the heat by using umbrellas and fans, gathering in shaded areas and staying hydrated. Paramedics were also seen assisting an overheated attendee.
Jennifer Wells of Southwest Philadelphia came prepared with a visor and water.
"Unity. We need that right about that. Peace and unity," Wells said.
Dee Fass of North Philadelphia sold rainbow sun visors to the crowd.
"Keeps sun off your head and rain off your brain," Fass said.
Because of the extreme heat, organizers modified the traditionally outdoor event and added additional cooling resources.
"More misting fans, more misting tents, added water, etc., but then we have made some changes to our events," said Nicole Allen, chief operating officer of Wawa Welcome America Inc.
Some activities, including the Hoagies for Heroes competition between the Philadelphia Police and Fire departments, were moved indoors. Following his department's win, Police Commissioner Kevin Bethel emphasized the importance of heat safety.
"Heat safety is paramount for us," Bethel said.
Bethel said the heat presents additional challenges for officers working outdoor events throughout the holiday week.
"It's going to be a challenge because we wear the bulletproof vests that adds another layer of heat and temperature to their bodies and weight to their bodies, so we're very much conscious of that, making sure our men and women are hydrated," he said.
Wawa Welcome America also announced additional changes because of the heat, including canceling the scheduled All-American Block Party and shortening the parade route.