Urban heat resilience is an increasingly critical issue, as extreme heat kills more people in the United States than any other weather-related disaster (BERKO 2014). The Intergovernmental Panel on Climate Change (IPCC 2022) warns of prolonged stretches of high temperatures, which pose greater health risks than isolated extreme heat events. Researchers now conceptualize the urban heat island as an “archipelago” of hot spots heterogeneously distributed across cities, with higher temperatures concentrated in areas dominated by concrete and asphalt, while cooler zones are found around trees, parks, and shaded open spaces (BORUNDA 2021). The growing intensity, duration, and frequency of heat waves have disproportionately impacted underserved populations, who face increased vulnerability. This paper investigates how mapping and visualization can uncover thermal disparities within urban environments. We developed a vulnerability assessment method in collaboration with the City of Omaha Planning Department, which is simultaneously creating a Climate Action Plan. Using Landsat 8 satellite imagery, we calculated and mapped Land Surface Temperature (LST) to identify Omaha, NE's most significant heat islands. To better understand heat disparities within these “islands,” we mapped and compared environmental/health, social/economic, and physical infrastructure data against city-wide metrics. Our analysis focused on average surface temperature, total population, percentage of ethnic minorities, poverty rate, median household income, unemployment rate, and indicators of physical and mental health vulnerability. The results indicate that in all identified “islands,” average surface temperature and poverty rates exceeded city averages. The areas of 75 North, Southside Terrace, and Downtown showed the highest vulnerability scores, with elevated surface temperatures, poverty rates, minority percentages, and unemployment rates, while household income, physical health, and mental health outcomes were lower than citywide averages.