The Reason It’s So Muggy In The Midwest? Corn.
Corn is literally everywhere you turn around here and some scientists say you can blame the crop for the uncomfortable mugginess of late summer in the Midwest. According to this story from The Telegraph "corn sweat" is a phenomenon that's been known by weather folk for quite sometime now.
Basically how it works is the ubiquitous plant soaks up a ton of moisture in the ground and then beads up on its broad leaves. This moisture then evaporates in the air and contributes to the high humidity all over the corn belt. Due to the massive amount of corn that is planted from Iowa and other places means that this added humidity will affect the weather in Chicago just as much as it will right on the farm.
The term is scientifically called evapotranspiration, but I'll keep calling it corn sweat, and it's becoming a bigger problem each year. The U.S. planted 7% more corn this year than last and is at its third highest acreage since 1944. Soybeans also contribute to this phenomenon and are being planted at a record rate.
I'm personally torn on this issue. On one hand I am NOT built for heat and usually throw up the white flag of air conditioning once the mercury hits 75. On the other hand corn is great. I mean have you had elotes? Looks like this is just something we Midwesterners will have to continue to deal with just like we learned to deal with the smell of pig farms while driving through the country.