Deadly Heat from Climate Change

July 16, 2025 News

By Elyse Schaeffer

Monday, June 23, 2025 was the third consecutive day in St. Louis where temperatures were over 90 degrees and the heat index was more than 100 degrees with humidity. Our community saw first hand how dangerous these conditions can be when Shauna Thomas, a 55 year old woman, was found dead in her apartment in St. Ann that evening (1).

Most devastating is that her death was likely preventable. St. Louis Public Radio reported that Ms. Thomas’ apartment did not have air conditioning when first responders arrived. Her electricity had been shut off by Ameren on June 11.

From June 1 to September 30, electric utilities in the state of Missouri are not allowed to disconnect customers within 24 hours of a forecasted temperature above 95 degrees or predicted heat index over 105 degrees. Starting August 28 of this year, that window will be expanded to 72 hours. Even under the new law, the more than 200,000 Missourians who are already behind on their Ameren bills can be disconnected outside of that window, leaving those like Ms. Thomas–who was disconnected on a day where the temperature was 88 degrees–vulnerable.

St. Louisans in particular need more help staying safe during extreme heat. The number of days in our city where the “feels like” temperature is 108 degrees or higher will triple in the next 30 years (2). In that same timespan, we expect to see 50 days per summer where the temperature reaches 100 degrees–nearly doubling what we expect this summer. We could even see the temperature reach 125 degrees in St. Louis in the next three decades(3). Heat is already the deadliest weather event in the country (4). Higher temperatures are certain to make this worse.

Additionally, St. Louisans are disproportionately likely to have a high energy burden, meaning that someone pays more than 6% of their income for their electricity and gas (5). Energy burden is especially high in predominantly Black, historically redlined, low income neighborhoods. Black adults are also more likely to die during extreme heat events than their white counterparts (6). The very same St. Louisans who are more likely to be in danger from heat death are reeling from the EF-3 tornado on May 16. Though numbers have yet to be published, the decreased shade due to tree loss during the storm is sure to exacerbate high bills in already energy burdened neighborhoods. Mature, strategically placed tree canopy can cool a city by 4-5 degrees F (7). 

In the wake of that recent tragedy, Ameren showed us they have the power and financial capability to provide much needed relief. After the storm, the company granted a disconnection moratorium for those affected by the tornado (8). Disconnections are set to resume on August 1, 2025. 
Today, 36 area organizations, including Missouri Coalition for the Environment, have joined together to say this is not enough (9). Dangerous temperatures persist throughout August in St. Louis, which means lives are still at risk, especially in tornado affected neighborhoods. Over the last five years, the average temperature in St. Louis in July is 81 degrees while in August it is 80 (10); likewise alltime record highs in July average 106 degrees while August record highs average 104 (11). Moreover, August is a more deadly month for heat in Missouri than June (12). Our colleagues at the Sierra Club are leading the charge in asking that Ameren expand this disconnection moratorium through September and forgive all debt for customers in energy burdened neighborhoods within half a mile of the May 16 tornado’s path (13). We hope you will join us in telling Ameren that our lives are more important than your profits. They have the power to end disconnections and prevent more tragedies like this one from happening again. Please click the link below to add your name.

1. Grumke, Kate. “A St. Ann woman died in her hot apartment. Ameren had shut off her power,” St. Louis Public Radio, June 25, 2025. https://www.stlpr.org/health-science-environment/2025-06-25/st-ann-woman-died-heat-wave-apartment-ameren-shut-off-power 
2. First Street Foundation. “Does St. Louis Have Heat Risk?” Accessed July 14, 2025. https://firststreet.org/city/st.-louis-mo/2965000_fsid/heat 
3. Ibid.
4. Adams-Fuller, Terri. “Extreme Heat Is Deadlier Than Hurricanes, Floods and Tornadoes Combined,” Scientific American, July 2023. https://www.scientificamerican.com/article/extreme-heat-is-deadlier-than-hurricanes-floods-and-tornadoes-combined/
5. DeRose, Jenn and Tori Cheatham, St. Louis Energy Burden Report: How Geography, Income, and Race Factor into Energy Costs for St. Louis Families, January 2025, pp. 5. https://www.sierraclub.org/sites/default/files/2025-01/stlouisenergyburdenreportjan2025_0.pdf
6. Khatana, Sameed Ahmed M., et. al, “Projected change in the burden of excess cardiovascular deaths associated with extreme heat by mid-century (2036–2065) in the contiguous United States,” Circulation 148(20), November 14, 2023, 1559-1569. doi:10.1161/CIRCULATIONAHA.123.066017.
7. de Andrade, Matheus Gouvea. “How Medellin is Beating the Heat with Green Corridors,” BBC September 22, 2023. https://www.bbc.com/future/article/20230922-how-medellin-is-beating-the-heat-with-green-corridors
8. Grumke, Kate. “In tornado’s wake, Ameren won’t cut off St. Louisans behind on bills,” St. Louis Public Radio, May 27, 2025. https://www.stlpr.org/news-briefs/2025-05-27/tornados-ameren-missouri-st-louis-pause-disconnections
9. You can view the letter and full list of organizations here: https://www.sierraclub.org/sites/default/files/2025-07/amerenmissouritornadoopenletter_07_16_2025.pdf
10. National Weather Service. St. Louis, MO – Monthly and Seasonal Mean Temperature, accessed July 14, 2025. https://www.weather.gov/media/lsx/climate/stl/temp/temp_stl_monthly_seasonal_averages.pdf
11. National Weather Service. Saint Louis, MO – Daily Record High, Lowest High, Low, and Highest Low Temperature, accessed July 14, 2025. https://www.weather.gov/media/lsx/climate/stl/temp/temp_stl_record_hi_lo.pdf
12. Between 1980-2016, there were 860 hyperthermia deaths in Missouri in June while there were 965 in August. Missouri Department of Health and Senior Services, Hyperthermia, pp. 16. https://health.mo.gov/living/healthcondiseases/hyperthermia/pdf/stat-report.pdf
13. DeRose, Jenn. “Letter: With deadly heat rising, Ameren must end disconnect policies,” St. Louis Post Dispatch, July 2, 2025. https://www.stltoday.com/opinion/letters/article_9e96422d-912e-4c14-a5cf-dc52f0931957.html