The air in the middle of the country for the last week or so has been, well, juicy. Dew points are in the mid-70s as far north as Fargo, even in the middle of the night. This is very uncomfortable, especially for the Nordic persons in the Upper Midwest, a hearty people known more for their winter resilience. There is a reason for this boost in humidity.

Corn.

Part of the respiration process for plants includes moisture leaving through evaporation. I’m not a biologist, so I won’t labor to explain that part of it to you I will say that the amount of evaporated moisture goes up with the volume of plants. Certain types of plants also produce more moisture.

Broad leafed crops, particularly corn, is an efficient evapotranspirator, and later in the season, when corn is at its heartiest for the season, local moisture climbs. Corn is a cash crop in heartland, and the elevated dew points seem to be most impacted in Iowa and Illinois. As temperatures start to cool ahead of the harvest, the moisture can be so much that it leads to overnight fog until it arms up in the afternoon.

This time of year, though, it ha a destabilizing effect on the atmosphere. When even a weak system moves into such a moisture rich environment, storms erupt with even more rain, and potentially some additional wind and hail, because of the updrafts enhanced by the supersaturated air. Of course, more and heavier rain can only lead to one thing.

More corn.