Evaporation from cornfields boosts heat index in mid-Missouri

The sun's beating down and winds out of the south continue to increase the moisture felt in Mid -Missouri leading to an increase in the heat index.

On top of this, some micro-climates in Mid-Missouri are feeling a little bit warmer. These micro-climates are cornfields, and it's caused by evaporation from these tall plants.

According to the US Geological Survey, one acre of planted corn can add up to 4,000 gallons of water in the atmosphere in a single day.

In the state of Missouri, about 3.45 million acres of corn were planted alone in 2023. This could mean up to 13.8 billion gallons of water could be added to Missouri air each day. In comparison, the average swimming pool in the US can hold close to 20,000 gallons of water.

Although most of the moisture in our atmosphere is fueled by moisture carried by the low level jet stream from the Gulf, this is still a significant amount of water being added to local fields around you, creating small microclimates.

The way this process works is corn needs more water to be able to survive during the late summer months. Corn will draw more water from the ground through their roots into the stem. Eventually after that water is done following the photosynthesis process, it'll be released back through their leaves which will then evaporate. This will increase the moisture in the atmosphere that could be felt by the increase in humidity. Eventually, this will lead to an increase in the heat index which, according to the National Weather Service can sometimes surge up to 15 degrees higher in these local microclimates.