Environment

Withering heat in Louisville this week halted races at Churchill Downs, killed fish at a pond in Cherokee Park and sabotaged a baker’s artisan sourdough.

Sweltering temperatures took hold of the city on Monday with the heat index reaching 110 degrees before breaking a century-old record Wednesday with a daily high of 97 degrees.

Over at Logan Street Market in Shelby Park, James Bridges had to shut down his retail sales at Grainwright Bakery two days this week because it was too hot to properly bake bread for his artisan sourdough. 

“The ideal desired dough temperature is around 75 degrees,” he said. “Warmer than that and you’d struggle to build any strength in it because the dough is so soupy.”

Interim State Climatologist Megan Schargorodski said the last time Kentucky experienced a similar heat wave was back in 2012.

That event caused a drought, but recent rains have so far warded off dry conditions this time around. Schargorodski said the extra precipitation has also made it especially humid, pushing the heat index well over 100 degrees in many parts of the state, including Louisville.

“You’ll notice the heat indexes have been really high even though the temperatures, while in the 90s, have not surpassed 100,” she said.

Victoria Lujan said she started sweating around 7 a.m. Thursday while making deliveries for Office Depot in downtown Louisville. To beat the heat, she tries to get as much done as possible before noon. 

“Sometimes I’ll put a frozen water bottle in my back pocket because it’s almost like a little A/C,” she said.  “Sometimes, I’ll bring a towel to keep the sweat off me, cold towels, because now with the gas prices you can’t even really idle the trucks anymore.”

Louisville and surrounding communities offer a number of indoor, air-conditioned spaces known as “cooling centers” where people can cool off to avoid heat-related illnesses. Meanwhile, people struggling to pay their utility bills have until Friday, June 17, to apply for the Low-Income Home Energy Assistance Program (LIHEAP) – if the city still has federal funds.

These are the kinds of adaptations cities will have to consider to become more resilient in the face of a changing climate.

Greenhouse gases from burning fossil fuels are increasing global temperatures and the frequency of extreme heat events across the world. It’s most apparent in summertime, with average temperatures rising across the country.

The climate research non-profit Climate Central has found average summer temperatures in Louisville have warmed 3.4 degrees since 1970.

Climate Central

Hotter summers lead to more heat-related illnesses causing more than 11,000 deaths across the country between 1979 and 2019, according to the U.S. Environmental Protection Agency.

Hot, sunny days also exacerbate poor air quality conditions. Louisville for years has had problems with ground level ozone. Just this week, the city’s air pollution regulations issued multiple air quality alerts.

The excessive heat helps trap harmful pollutants closer to the earth’s surface and contributes to the formation of ground level ozone, which can cause coughing, shortness of breath and increase the frequency of asthma attacks. 

Temperatures are expected to cool off this weekend as a rain system moves through, but how much it cools off depends on where it hits in Kentucky, Schargorodski said.

The reprieve may be a brief one though with temperatures forecast to hit the triple digits on the first official day of summer, June 21. 

Ohio Valley Resource Reporter Liam Niemeyer contributed to this story

Ryan Van Velzer is WFPL's Energy and Environment Reporter.