What is corn sweat? A Midwest heat wave is causing humidity to skyrocket.

Ah, yes, late August in the Midwest: a time for popsicles by the lake, a trip to the county fair, and, of course, extreme humidity made more miserable by … corn sweat.

Corn sweat. It’s a thing! And people are talking about it.

The term refers to the moisture released by fields of corn during…