Temperatures in the 90s, along with high humidity and dew points, have been joined by an agricultural phenomenon called corn sweat that is making the current heat wave this summer even worse.
The actual term for corn sweat is evapotranspiration, where water is released from the plant’s leaves and helps the plants move water.
Andy Lesage, a meteorologist with the National Weather Service in Paducah, says all types of vegetation can hold and release water, but it’s most common in corn, which in turn affects the weather.
click to download audioThe evapotranspiration average for corn is 3.5 to 5mm a day. In soybeans, it’s 4-6 mm a day, while alfalfa averages 6 to 8 mm a day.
Because more corn is grown in Midwestern states such as Illinois and Iowa, the corn sweat is more common there, but it still affects western Kentucky.
click to download audioLesage also says the above-average rain western Kentucky has received this year is contributing to more water vapor in addition to the corn sweat.
click to download audioDuring the growing season, one acre of corn can release 3,000 to 4,000 gallons of water a day. In Christian County, that can equate to 280 million gallons a day. In Todd County, that’s 168 million gallons a day. Caldwell County’s corn crop releases an average of 91 million gallons a day, and Trigg County around 56 million gallons a day.
You can expect corn sweat to be prevalent in some western Kentucky areas for at least the next 3-4 weeks until corn harvest season.
