How ‘Corn Sweat’ Makes Summer Days More Humid

“Under conditions like we have now where it’s very warm to begin with, and the atmosphere has a significant amount of moisture in it already, the crop is just adding moisture to that, making conditions feel even more humid,” said Dennis Todey, director of the U.S. Department of Agriculture’s Midwest Climate Hub. “When [water] converts from that liquid form to that gas form, it takes a lot of energy with it,” said Joe Lauer, a professor and corn agronomist at the University of Wisconsin. The process is technically called transpiration or evapotranspiration, analogous to perspiration in animals.