Another crushing heat wave is hitting the United States this week. The so-called “dog days of summer” are in full swing for much of the eastern two-thirds of the U.S., as a heat dome over the Mississippi River and Ohio River valleys gradually builds later in the week, according to the Weather Prediction Center (WPC) at the National Oceanic and Atmospheric Administration (NOAA).

One unlikely culprit for the high humidity, especially in the Midwest, is “corn sweat.”

Corn sweat is the term used to explain how corn, like other plants, excretes water vapor through its leaves via a process called evapotranspiration, which increases humidity in regions where corn is grown during the summer—namely, the Corn Belt, which stretches from North Dakota and South Dakota east to Ohio,........

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