If it felt like this summer was warmer than normal in Utah, you’re right.
Cedar City, Brigham City and Escalante all experienced their hottest summers on record, based on combined high and low temperatures. That’s for the astronomical summer that this year ran from June 20 to Sept 22.
Kanab had its second-hottest summer on record, and Bountiful, its third-hottest. The average temperatures in Salt Lake City, St. George and Provo each ranked among the cities’ top five warmest.
The heat also was a significant increase from Utah’s typical summer weather.
The average temperatures in Salt Lake City, Brigham City, Kanab and Cedar City were all more than 3 degrees warmer than the 30-year normals from 1991-2020.
This type of extreme heat is now becoming a new normal for Utah — a local example of how climate change fueled by greenhouse gas emissions is elevating temperatures across the globe. But that isn’t the only factor at play, said National Weather Service Meteorologist Matt Jeglum.
“We would expect with climate change, that temperatures — maximums and minimums — would be warming. But we also have been growing a lot, so there's an urbanization factor.”
That’s just a fancy way to say concrete gets — and stays — hotter than the natural landscape. Utah’s population growth in recent decades has created more heat islands within cities that push temperatures higher and endanger the health of residents.
That’s especially true with rising low temperatures, Jeglum said. For example, Salt Lake City had 17 nights this summer when the overnight low didn’t drop below 75 degrees. In all the summers from 1928 through 2000, that only happened 29 times.
“We tend to focus on the maximum temperatures during the day as kind of the headline,” he said. “When you're looking to assess the impact of a heat wave on a population, you definitely need to consider the overnight minimum as much as you do the daily maximum.”
Still, this summer also had its share of extreme daytime highs.
Out of 94 possible days, the temperature in St. George hit 100 degrees on 76 of them. The city also set a new heat record for July and ended up with an average summer high of 102.8 degrees — 2.96 degrees warmer than its 30-year normal.
Salt Lake City, Brigham City and Cedar City all saw similarly hot high temperatures, each ranking among the cities’ top five warmest.
July 11 was the peak of extreme heat this summer in Utah, Jeglum said. On that day, Cedar City hit 103 degrees, making it the city’s fourth-hottest of any day on record. The same day, temperatures soared to 115 degrees in St. George and 106 degrees in Salt Lake City — just one degree shy of the city’s all-time record.
While it’s possible Utah could still catch a cooler summer every once in a while in the coming years, Jeglum said it’s likely that we’ll see more heat like this in the future.
“Both in terms of the climate change signal and the urbanization signal, the dice are going to be loaded toward these summers that are hotter than what we might have seen typically in the 1950s, 1980s, even 2000s.”

Even though summer has officially ended, the year’s heat may not be over. The National Weather Service expects high temperatures in Utah to be up to 10 degrees warmer than normal through the end of September, Jeglum said.
The latest seasonal outlook for this fall from the National Oceanic and Atmospheric Administration also predicts above-average temperatures to continue in Utah from October through December.
As it gets closer to winter, however, Jeglum said there’s a silver lining to that forecast.
While above-average October highs might mean more 90-degree days for a place like St. George, other parts of the state could end up with pleasant weather.
“In Salt Lake, that's going to be upper 70s. I don't think anybody's going to complain about that.”