Urban Heat
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Urban Heat
Warmer Nights
With a changing climate, we can also expect more nights over 80 degrees as higher levels of humidity will hold more of the heat that builds up in the daytime. At the current rate of change, we can expect 80+ degree nights to be the average rather than an extreme.
Warmer nights will mean that our most vulnerable residents will not be able to escape the heat of the day as they have in the past. Air conditioning will continue to run throughout the night for a greater part of the year, placing a larger burden on our energy supply.
Urban Heat
Prioritizing Action in the Neighborhoods That Need It Most
The South San Antonio neighborhood, known as South San, experiences some of the most intense urban heat island (UHI) effects in the city—a phenomenon where paved surfaces and limited vegetation trap heat and raise local temperatures (Learn more about UHI below). According to Bexar County, climate projections indicate that the neighborhood will likely see increased annual temperatures and up to 110 days per year with high temperatures above 95° F by the 2050s, heightening extreme heat risks.
In South San, high social vulnerability compounds the challenge: residents face limited access to health care facilities and fresh food, inefficient home cooling, language barriers, and high utility costs. Older adults, people with disabilities, and children are especially at risk. This heat vulnerability map highlights South San as a priority area for heat resilience action.
Urban Heat
The South San Heat Resilience Project
To address urban heat in South San, the City of San Antonio partnered with Fuerza Unida and Adaptation International to launch the South San Heat Resilience Project, supported by a $96,000 grant. This pilot project empowers residents to shape community-driven cooling solutions and build local leadership in climate resilience.
As part of this project, the City identified Priority Action Sites within the South San neighborhood for infrastructure improvements and climate resilience programs. By fall 2025, work is already underway at many of these locations and beyond:
- The South San Walking Trail gained a new outdoor water fountain in July 2025, and a community-designed Art as Shade Structure is in progress, slated for completion in early 2027.
- At the South San Community Center, additional water fountains and picnic table shade structures will be installed in October 2025.
- A Cool Corridor microgrant program will launch this fall in partnership with RevitalizeSA.
- A Cooling Committee formed in May 2025.
- A Green Youth Workforce Development Pilot begins this October.
- Climate Justice Promotora training programs will launch in November.
Together, these initiatives are building lasting resilience in South San by combining infrastructure improvements, community education, and climate justice leadership.
This project is ongoing and will continue to develop as the City and its partners work with the South San community on the above infrastructure improvements and engagement programs.
Take action: Explore San Antonio Urban Heat Island resources to help you and your community stay safe and cool.
Urban Heat
SA Heat Maps
Learn about the City's urban heat island initiatives, explore interactive maps, and prepare for summer.
Urban Heat
Cool Pavement Reduces Urban Heat Island Effect
San Antonio can get hot. Some parts of the city, especially those with a lot of buildings and roads but not much natural shade, can get even hotter – sometimes, by as much as 20 degrees!
This is called the “urban heat island” effect. The asphalt used to pave roads traps heat and releases it at night, making a hot city even hotter.
Solution
The water-based asphalt treatment known as cool pavement reflects more sunlight and absorbs less heat, thereby reducing spikes in temperature at night. It’s safe to use, containing no harmful chemicals, enhances the life of the pavement, and is compatible with traditional asphalt. Cool pavement looks different – it’s lighter and grayer in color.
The City of San Antonio continues to lead by example with the continued expansion of the cool pavement treatment applications citywide.
Progress
In 2021, San Antonio became the first City in Texas to use cool pavement. Then, in 2023, the City expanded this initiative by applying cool pavement products to sections of roadway in all 10 Council Districts. In 2024, Treatments were applied to 10 sections of roadway in Districts 3, 5, & 6. Planned for 2025, 110 streets across all 10 Council Districts will receive the Cool Pavement product application.
Fiscal Year | Streets Treated | Total Treated Miles |
2023 | 10 | 2.7 |
2024 | 10 | 2.2 |
2025 | 110 | 22.35 |
Find out more about cool pavement and view the projects' locations here on the Public Works Cool Pavement Program page.
In partnership with UTSA the program has studied the locations and treatments for their potential to cool the city down. Researchers have tested the effectiveness of three separate cool pavement treatments in 2023 and 2024. The 2023 study showed an average surface temperature reduction of 3.58 degrees. In 2024, the average surface temperature reduction was between 6°F and 12°F.
For more information, check out the latest reports:
Continued Evaluation of Cool Pavement as an Urban Heat Mitigation Measure and Phase II: Evaluation of Cool Pavement Surface Treatments Using Friction, Texture and Adhesion Properties)
Overall, the results from 2024 agreed with the 2023 report and studies conducted in Phoenix and Los Angeles, which also documented the clear potential for cool pavement to reduce surface temperature.
2023 research reports:
Cool Pavement Testing Report (02/12/2024)
San Antonio Cool Pavement Report (02/08/2024)
Urban Heat
Heat and Air Quality
San Antonio has made great progress on improving local air quality, in particular reducing ground-level ozone. Our ability to control ozone levels through pollution reduction will be challenged as extreme heat days create better conditions for ground level ozone to form.
Persistent exposure to poor air quality is a chronic stressor for some communities which creates vulnerability to other kinds of threats, including worse outcomes associated with COVID-19. The risk associated with the combination of heat and poor air quality is a critical reason why San Antonio is working to reduce emissions and prepare for climate impacts to improve public health and overall community resilience.
Urban Heat
Protecting Vulnerable Populations
One way to reduce vulnerability is to reduce exposure to impacts like heat waves with cooling centers. The City of San Antonio has 52 locations of cooling centers around the region. The other way is to take care of the underlying health stresses some members of our community face.
San Antonio’s Mobile Integrated Healthcare program is one way that we’re reaching into the community proactively to improve health and wellness among our most vulnerable populations to help them better manage all kinds of threats, including those posed by climate change.
Urban Heat
City Cooling Centers
One of the best ways we can prevent heat related illness and protect public health is to provide accessible public cooling centers. That's why the City of San Antonio has opened cooling centers around town for residents to access.
Use the map embedded here to find a cooling center near you and find all the cooling resources provided by San Antonio Emergency Management on the Beat the Heat program website.