A dangerous combination of extreme heat and humidity will grip the central United States this week, with heat index values expected to reach as high as 115 degrees Fahrenheit due to a heat dome and a phenomenon known as “corn sweat.”
Weather experts warn that states across the Corn Belt including Missouri, Minnesota, Iowa, Indiana, Illinois, and the Dakotas will experience some of the most oppressive conditions in the country. The Corn Belt is particularly vulnerable due to its dense agriculture, especially corn crops, which play a surprising role in boosting humidity levels.
The region is already facing higher-than-average humidity this July, and now “corn sweat” is adding to the discomfort. Corn plants release moisture into the air through their leaves in a process called evapotranspiration, similar to how humans sweat. This natural release of water vapor significantly increases the local humidity, especially during the hot summer months.
As a result, humidity levels in these Midwestern states may rival or even exceed those in typically muggy areas like Florida.
The combined effect of the heat dome a high-pressure system trapping heat near the surface and corn sweat will make outdoor conditions dangerous, especially for vulnerable populations. Authorities urge residents to take precautions, stay hydrated, and limit outdoor activity during peak heat hours.
