For the Washington Post, Kasha Patel and Naema Ahmed mapped the change in summer time.
The analysis, conducted by climatologist Brian Brettschneider, examined the hottest 90 days of the year from 1965 to 1994 and compared their frequency over 1995 to 2024. He found that the temperatures that used to kick off the hottest three months of the year are expanding beyond the calendar definition of summer.
I like the interactive bit at the beginning to enter your ZIP code. It’s speedy.