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Corn sweat explained: Why Midwest humidity is so intense

A single acre of corn can release up to 5,000 gallons of water into the atmosphere each day. That extra moisture raises humidity and dew points, making hot days feel even more uncomfortable.

Corn sweat sounds like a joke, but millions of corn plants release moisture into the air, making Midwest summers even sticker.

Corn sweat is an informal term for evapotranspiration, a natural process in which plants absorb water from the sol and release water vapor through tiny pores in their leaves. It’s like how humans sweat as moisture evaporates, it helps cool the plant.

A single acre of corn can release up to 5,000 gallons of water into the atmosphere each day. That extra moisture raises humidity and dew points, making hot days feel even more uncomfortable.

While corn sweat is essential for plant health; it can add to the misery of summer heat waves. Add in the July sun, a prolonged stretch of temperatures in the nineties, and heat indices climbing well above a hundred degrees, and summer can feel downright relentless.

While you can't stop corn from sweating, knowing what's behind that sticky air might make the next heat wave a little less mysterious. Stay up to date for more interesting weather facts online at South Carolina ETV and Public Radio.