The hot weather is expected to break late Wednesday or early Thursday.
Philadelphia city government activated special summer-heat programs, and the Philadelphia Corporation for Aging was operating a Heatline service for seniors from 9 a.m. to midnight. The number is 215-765-9040.
In the city, residents, tourists and workers coped in various ways. At mid-afternoon at JFK Plaza in Center City, young girls dipped their feet in the fountain and old women fanned themselves with newspapers.
Hannah Utain-Evans and her friend Alaina Ewins, students at the Asian Arts Initiative, positioned themselves so that sprays from the fountain blew toward them.
"We also walk into shops but don't buy anything, to get some air-conditioning," Utain-Evans said.
At the Shore, the only place to find relief was right at the shoreline. Temperatures ranged from 80 to 85 degrees at the water's edge.
"We played hooky," said Sandra Michaels, 48, as she sat with her husband, Bob, 53, on a beach in Ocean City's north end. The Michaelses own a window-washing business in Vineland, N.J.
"It was too hot to even think about washing windows today," Bob said, "so we packed up and came here for the day, instead."
Lindsey Rigoli and Claire D'Angelo, 17-year-old Philadelphians spending part of the summer at a house in Margate, were not so happy.
"We went to the beach this morning, but it was so hot, I started to get a headache, so we came in," D'Angelo said. "Now we're doing some shopping and getting ice cream before we head back into the air-conditioning at the house."
Philadelphia's acting medical director, James Dean, urged residents to visit "older friends, relatives and neighbors to ensure that air conditioners or fans are working, and homes are adequately ventilated." He noted that the victims in a heat wave tend to be "older people and those with pre-existing medical conditions."
No heat-related deaths were reported in the region Monday. Deaths tend to occur at the end of a sustained period of hot weather, after the heat has had time to build up inside homes.
With the excessive-heat warning continuing into Tuesday, officials urged area residents to use air conditioners and fans, wear lightweight clothing, drink plenty of non-alcoholic liquids, shower or bathe in water near skin temperature, and avoid working or playing in the sun as much as possible.
To help seniors cope with the heat, Peco Energy plans to give away 500 fans Tuesday at locations in Philadelphia, Doylestown, West Chester, Eddystone and Norristown.
Contact senior writer Larry Eichel at 215-854-2415 or firstname.lastname@example.org.