At the end of the century, Austin’s average summertime high temperature could be six degrees above today’s average high of 97 degrees. And it may be hotter than 110 degrees in the city more than 20 days a year; even one day that hot is a rarity now.

Those are among the findings of a study that the city commissioned last year on the impact of climate change.

“If you’re going to build a substation that’s going to cost tens of millions of dollars but it’s not going to operate over 110 degrees, it’s really important to be thinking about that now,” said Zach Baumer, the city’s climate program manager. While other Texas cities have looked at climate change issues, none have done comprehensive studies of their impact.

The study, which Mr. Baumer said cost less than $20,000, was the start of Austin’s efforts to apply global climate projections specifically to the city. Reports from groups like the Intergovernmental Panel on Climate Change focus on global temperature and rainfall models, which for Austin are “just not useful to actually make decisions,” Mr. Baumer said. With forecasts specifically related to Austin, “we can start to put plans in place and act in ways that make sense, and not just sort of generalize, ‘Oh, we’re doing something about it,’ ” he added.