When Blackouts Occur During Heat Waves, Austin Homes Pose Major Risk

February 10, 2026

A map of an unnamed neighborhood shows properties colored according to indoor heat risk. — The average daily heat risk in a suburban Austin neighborhood, with dark red signifying higher risk and yellow lower risk. Credit: Calvin Lin

If the power goes out during a heat wave, there’s nowhere more dangerous to be than where people spend most of their time — indoors.

A new study led by researchers at The University of Texas at Austin is the first to assess the indoor heat vulnerability for each single-family home in an entire city. The research used Austin as its testbed, but the approach can be applied to most cities in the U.S.

The researchers found that if the power were to go out during a heatwave, 85% of Austin’s single-family homes would pose significant risk of death to an elderly person inside. For the younger population, the current risk is far less — about 15%. The Rundberg and St. John neighborhoods are the most vulnerable overall, according to this study.

The study was published in the journal Building and Environment. It’s a project that was facilitated by the UT-City CoLab, an initiative that brings together UT researchers, Austin city officials and community members to build climate resilience. This is part of a larger collaboration between UT and the City of Austin that connects University research with community needs.

Dev Niyogi, a professor at the UT Jackson School of Geosciences and CoLab co-lead, said that this study helps pinpoint locations that would benefit from heat mitigation efforts akin to what is already done for homes near the floodplain.

“We are elevating the problem. Rather than saying, ‘Austin is hot. We need to cool it,’ we’re saying, ‘Here’s where we need to focus. And here are the kind of solutions we can do,’” Niyogi said.

Marc Coudert, climate resilience and adaptation manager for Austin Climate Action & Resilience, said that this city-wide model is just the starting point.