Is This the End of the Summer Vacation as We Know It?

You can’t escape the orange. That’s what travelers this summer have been reckoning with — swaths of tangerine, traffic cone and burnt sienna on maps indicating record high temperatures around the globe. Four concurrent heat domes from the southern United States to East Asia descended on millions — Phoenix residents enduring 31 days of 110-degree-plus temperatures. Italians in more than a dozen cities under extreme weather warnings. And in South Korea, at least 125 people were hospitalized for heat-related conditions at the World Scout Jamboree.

In Florida, it got so bad in June that Jacki Barber, 50, a clinical social worker and eighth-generation Floridian, canceled a beach trip to St. Augustine. “The water temperature was like 89 degrees,” Ms. Barber said.

“We’re used to hurricanes ruining plans, tropical storms, even just bad thunderstorms,” she said. “But I don’t recall ever looking at anyone and saying ‘It’s too hot to go to the beach.’”

As the summer travel engine kicked into high gear this year, it wasn’t just the scorching heat affecting…