Summer 2026 Breaks U.S. Heat Records with Multiple Cities Exceeding 100-Degree Days

This summer was America’s hottest yet — and a new troubling analysis reveals several cities have seen more triple-digit temperature days than ever in 2026.

It may come as little surprise that the top five cities were mainly in the South, according to forecaster AccuWeather, with Dallas, Texas, taking the top slot at 52 days with sizzling temperatures above 100 degrees Fahrenheit (37.7 degrees Celsius). That’s more than double the city’s historical average and a far cry from the seven seen in 2025.

And the Lone Star State’s capital of Austin was a close second, with 48 scorching days. Last year, the city saw fewer than half that total.

Historic heat was also felt in Oklahoma and Kansas, with Oklahoma City ranking third, Tulsa coming in fourth, and Wichita taking fifth.

Oklahoma City only had one day at or over 100 degrees in 2025 — but 35 this year, per data.

Many cities from coast to coast have tied or broken annual records for the number of days at or above 100 degrees.

“Lander, Wyoming, has tied its record of three 100-plus-degree days, as has New York City's Kennedy Airport. Atlantic City has tied its record with four days. Miami tied its all-time record high of 100 degrees this summer, a feat that has only happened once before,” AccuWeather said.

Colorado, which was one of the states most affected by extreme heat this summer, has seen 27 days over 100 degrees this year, smashing a previous record set back in 2002.

Major heat domes settling over cities for days have played a role in broken records, including a September heat dome over the South.

Even as the heat begins to fade at the start of fall, climate change — and a strengthening super El Niño climate pattern — are making temperatures warmer nationwide.

That’s already been seen in changes in fall foliage and extensions to hurricane and wildfire seasons, with implications for the health of Americans.