Americans dipped into the water, went to the cinema and took tube trains just to have air conditioning relief from unrelenting heat that has killed at least 30 people across half the country.
The heat sent temperatures soaring over 100 degrees Fahrenheit (38 degrees Celsius) in several cities, including a record 105 F (40.5 C) in Washington, St Louis (106 F, 41 C), and Indianapolis (104 F, 40 C), buckled highways and derailed a Washington-area train even as another round of summer storms threatened.
The heat sent temperatures soaring in more than 20 states to 105 F (40.5 C) in Louisville, Kentucky, 101 F (38.5 C) in Philadelphia, and 95 F (35 C) in New York; besides Washington, a record of 104 F (40 C) was set in Sioux Falls, South Dakota,
At least 30 deaths were blamed on the heat, including nine in Maryland and 10 in Chicago, mostly among the elderly.
Three elderly people found dead in their houses in Ohio had heart disease, but died of high temperatures in homes lacking electricity because of recent power cuts, officials said. Heat was also cited as a factor in three deaths in Wisconsin, two in Tennessee and three in Pennsylvania.
Officials said the heat caused highways to buckle in Illinois and Wisconsin. In Maryland, investigators said heat probably caused rails to kink and led a green line train to partially derail in Prince George's County, Maryland, on Friday afternoon. No one was injured, and 55 passengers were safely evacuated.
Thousands of mid-Atlantic residents remained without power more than a week after deadly summer storms and extreme heat struck the area, including 120,000 in West Virginia and some 37,000 in the Washington DC suburbs. In the Washington area, utility company Pepco asked customers to conserve power, saying the heat was stressing the system.
“This is becoming a black swan of heatwaves, in the sense that it's such a long heatwave, such a severe heatwave and encompassing such a large area,” said Chris Vaccaro, spokesman for the National Oceanic and Atmospheric Administration.
In Manhattan, customers who stepped in to see Jiro Dreams Of Sushi at an IFC cinema were there for more than entertainment.
“Of course we came to cool off!” said John Villanova, a writer who was on his second sweaty T-shirt of the day - expecting to change again by evening.
He said that earlier, he went on a Manhattan tube train back and forth for a half an hour, with no destination in mind, “because it really keeps you cool”.
In cities around the Midwest and Mid-Atlantic region, people struggled to find ways to cope with the heat, but at least one such effort ended in tragedy.
In Aurora, Illinois, Gene Autry Pryor, 52, had been drinking with three adult friends near Veterans Memorial Island and jumped into the Fox River to cool off, police said. The man's friends lost sight of him after a few minutes and then spotted him floating face down and pulled him to shore. Mr Pryor died on Friday evening.
In Chicago, street magician Jeremy Pitt-Payne said he has been working throughout the three-day stretch of triple-digit temperatures, but acknowledged that he might doff the Union Jack leather vest by the end of the day, even though it was part of his British magician character along with the black top hat.
But he had a secret for beating the heat - he starts his shows at 2pm “when the Trump Tower is gracious enough to block out the sun” along his stretch of pavement.
At New York City's Penn Station, the air conditioning was falling short of full capacity. The doors were left wide open at a half dozen locations around the two-block-wide underground station.
“It's so hot I feel like I want to faint,” said Betty De la Rosa, 19, of the Bronx, who was working at a station doughnut shop.