If you’ve felt extra sticky during this summer in Bowling Green, especially this week, there’s a good chance corn is to blame. A little-known but scientifically backed phenomenon often referred to as “corn sweat” may be intensifying the heat and humidity across northwest Ohio. 

“Corn sweat” isn’t literal perspiration, but evapotranspiration: the natural process by which corn plants and surrounding soil exhale moisture into the air. Scientists have found mature corn can pump out thousands of gallons of water per acre every day. According to the Ohio State Extension Office, corn typically releases about 3,500 to 5,000 gallons per acre over a 1–2-day period. Other sources place the number at nearly 3,000 – 4,000 gallons daily per acre. 

Bowling Green sits deep in the Corn Belt, and during July and August those miles of ripening corn become humidifiers. As crops hit the tasseling and flowering stages, they release peak moisture into the nearby air at a time when heatwaves are also most likely. 

That extra moisture increases the heat index (how hot it feels) by combining with already warm air from weather patterns like southerly winds and heat domes, reports from The Washington Post. Local reports from the Ohio Valley note dew points climbing toward 80°F levels more typical of tropical climates according to WLWT. 

OSU experts caution “corn sweat” is just one player in a bigger climate picture. Large-scale atmospheric moisture such as Gulf-sourced air often contributes to more humidity. The extension office said during dry conditions, corn’s relative contribution diminishes. 

Still, the extension office says corn add-ons become meaningful during heatwaves, especially when plants are mature and actively transpiring, adding that uniform corn and soybean monocultures also exacerbate daytime heat retention and keep nights oppressively warm. 

As evening falls, Bowling Green residents often hope for relief but humid nights (with dew points in the upper 70s to low 80s) trap heat, limiting the drop in temperature according to a The Washington Post story and that can make overnight heat as stifling as daytime temps. 

The impact on heat index can be dramatic: a 95°F day with dew points in the upper 70s may feel closer to 105°F  – 110°F, which raises the risk of heat-related illnesses like exhaustion or heatstroke. 

For those without air conditioning or working outdoors, “corn sweat” isn’t just uncomfortable, it’s a public health concern. 

Local weather services suggest: 

• Monitoring heat index and dew point rather than just temperatures 

• Staying hydrated and remaining indoors during peak heat 

• Seeking cooling shelters if needed, especially during heat advisories