Phoenix Heat

The New York Times

Phoenix, which had 128 days at or above 100 degrees Fahrenheit in 2018, is one of the hottest and fastest-warming cities in the United States. Although it is on the leading edge, it is not alone: Most American cities are expected to drastically heat up in the next decades. Many may have summers with heat waves and triple-digit days — summers that resemble Phoenix today. 

Here in the valley of the Sun, that means work and play shift into the cooler hours. Neighborhoods thrum with activity at dawn and dusk when residents hike, jog and paddle board. In the hottest months, the zoo opens at 6 a.m., for the benefit of both animals and visitors. And across the city, certain construction work starts in the middle of the night — no only for the safety of workers but also because even some building Material can be affected by intense heat. 

— Marguerite Holloway