Complaints about summer heat are typical, but when people in Fort Collins and Greeley talk about feeling too hot, they’re not imagining things.

According to a new report from Climate Central that looks at how climate change is fueling a surge in dangerous heat days across the country, both Colorado cities are among the cities experiencing the biggest and fastest increases in summer heat.

Greeley ranks in the top 10 cities with the biggest increase in the number of average days above 100 degrees each year since the 1970s.

Fort Collins is on the list of top 25 cities with the biggest increase in days where the temperature climbed above 90 degrees each year since the 1970s.

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Science mag makes first endorsement in 175 years, taps Biden And summers in Boulder are just getting steamier — that city is number three on the list of the top 25 cities in America with the biggest dew point increase since 1970, which means it’s muggier.

While the muggy factor has increased in Boulder, it’s stayed the same in other Colorado cities during that same time. Alyson Kenward, a senior scientist at Climate Central who is an author of the report, speculates development such as swimming pools, fountains and golf courses add more moisture to the air.

“The other top cities on the list, Reno and Las Vegas in Nevada, like Boulder, have experienced significant changes in how the land was developed,” she said.

“Danger Days,” designated by the National Weather Service as weather that combines sweltering heat and humidity to create “real feel” temperatures above 105 degrees, are on the increase, according to the report.

If this climate change trend continues, “by the end of this century, summers in most Colorado cities will feel like it does today in southern Texas,” Kenward said.

She said Colorado has seven cities with populations — people under 5 and over 65 who are below the poverty level and don’t always have access to air conditioning — vulnerable to extreme heat: Denver, Boulder, Colorado Springs, Fort Collins, Grand Junction, Pueblo and Greeley.

Scientists created the report by analyzing historic summer temperature trends since the 1970s and creating projections for future extreme heat in hundreds of metro areas across the U.S.