Corn sweat: How the crop contributes to humid conditions

ST. LOUIS – You’ll notice over the last few days, the humidity has climbed, even excelling in some places, causing it to be extremely difficult to even be outside—even for a few minutes.

A wide swath of dewpoint temperatures in the low to mid 70s across the Midwest is indicative of extremely humid air. The reason for that? The corn.

Yes, corn!

With more than 14 million acres of corn in Missouri and Illinois, that’s contributed to the rise in humidity over the last few days. It’s a term you may or may not have heard of before called “corn sweat,” and it means exactly how it sounds.

Corn stalks sweat water, but they’re not sweating like humans do. Corn sweat is scientifically known as evapotranspiration. When it’s hot and it’s humid, corn doesn’t sit around and wait for a rainy day. They draw water from the ground with their roots into their stems and leaves, releasing it into the air as water vapor.

One acre of mature corn can release 3,000 to 4,000 gallons of water into the air. This evapotranspiration process has contributed to the high humidity. With a heat dome that moved in from Texas this past weekend, combining the humidity with the hot temperatures, it promotes dangerous heat index values.

For the latest news, weather, sports, and streaming video, head to FOX 2.