Illinoisans Endure 'Corn Sweats' Amid Extreme Heat

Have you noticed the recent high levels of humidity plaguing the Midwest? While it may be annoying, it is certainly not a coincidence. According to WGN9, there is a very logical explanation for the abundance of moisture in the air amid extreme temperatures, and it has everything to do with corn. Yes...corn.

As agricultural crops begin to grow, they release moisture through their leaves, making regions with a plethora of fields more susceptible to high levels of humidity, sometimes referred to as "corn sweat." The scientific name for the process is "evapotranspiration," and it encompasses the transference of water from "land to atmosphere" through soil and other plant surfaces (not just corn, though corn sweat is a very catchy term.) The US National Weather Service Central Illinois explained the phenomenon and detailed exactly how much water is used per day to water Illinois corn crops.

"Some of you have probably heard the term “corn sweat,” which is when corn (and really, other crops) give off moisture through their leaves as they move through the growing season. The scientific term for this is called evapotranspiration, and we are getting it in abundance! It’s a big part of why we are seeing such humid conditions and extreme heat index values. Did you know that mature Illinois corn crops give off over 35 BILLION gallons of water DAILY into the atmosphere. THIS IS ENOUGH WATER TO FILL OVER 52,500 OLYMPIC SIZE SWIMMING POOLS!"

WGN9 mentioned that "sweating" is the plants way of carrying water up through the roots to cool the leaves and keep the plant from drying up when the sun is out in full force. For more information on "corn sweats" and the entire process visit The National Library of Medicine's website.